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1
Bhoite, Sangram P., Jonghyuck Kim, Wan Jo, et al. "Understanding the Influence of Gypsum upon a Hybrid Flame Retardant Coating on Expanded Polystyrene Beads." Polymers 14, no. 17 (2022): 3570. http://dx.doi.org/10.3390/polym14173570.
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A low-cost and effective flame retarding expanded polystyrene (EPS) foam was prepared herein by using a hybrid flame retardant (HFR) system, and the influence of gypsum was studied. The surface morphology and flame retardant properties of the synthesized flame retardant EPS were characterized using scanning electron microscopy (SEM) and cone calorimetry testing (CCT). The SEM micrographs revealed the uniform coating of the gypsum-based HFR on the EPS microspheres. The CCT and thermal conductivity study demonstrated that the incorporation of gypsum greatly decreases the peak heat release rate (PHRR) and total heat release (THR) of the flame retarding EPS samples with acceptable thermal insulation performance. The EPS/HFR with a uniform coating and the optimum amount of gypsum provides excellent flame retardant performance, with a THR of 8 MJ/m2, a PHRR of 53.1 kW/m2, and a fire growth rate (FIGRA) of 1682.95 W/m2s. However, an excessive amount of gypsum weakens the flame retardant performance. The CCT results demonstrate that a moderate gypsum content in the EPS/HFR sample provides appropriate flame retarding properties to meet the fire safety standards.
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Srivastava, Anoop Kumar, Dharmedra Singh Rajput, Naveen Gupta, and Neeraj K Sharma. "Formulation and Evaluation of Nicorandil Floating Tablets Using Natural Polymers." Asian Journal of Pharmaceutical Research and Development 11, no. 2 (2023): 74–82. http://dx.doi.org/10.22270/ajprd.v11i2.1250.
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The present work described the pre-formulation and formulation development that led to the production of Nicorandil (NDL) floating tablets by direct compression of a homogeneous powder blend/ granules. In order to achieve the drug (NDL) release up to 24 hrs, rafting approach was selected. Studies have been carried out on rafting method by the use of natural polymers (sodium alginate, xanthan gum and guar gum) alone and their combination to get maximum rafting properties with superior drug release retarding activity. The results obtained in the rafting approach indicated that the polymer combination showed significant influence on rafting properties with maximum drug release retarding ability than individual polymers. In addition, the polymer combination of xanthan gum and guar gum resulted with maximum drug release retarding ability with poor rafting properties, whereas, the polymer combination of sodium alginate and guar gum resulted with predictable release behaviour (i.e. slightly lower retarding ability than the combination of xanthan gum and guar gum) with maximum rafting properties. As such the floating tablets prepared with rafting approach were recommended for oral controlled delivery of NDL.
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Bhoite, Sangram P., Jonghyuck Kim, Wan Jo, et al. "Expanded Polystyrene Beads Coated with Intumescent Flame Retardant Material to Achieve Fire Safety Standards." Polymers 13, no. 16 (2021): 2662. http://dx.doi.org/10.3390/polym13162662.
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The compatibility and coating ratio between flame retardant materials and expanded polystyrene (EPS) foam is a major impediment to achieving satisfactory flame retardant performance. In this study, we prepared a water-based intumescent flame retardant system and methylene diphenyl diisocyanate (MDI)-coated expandable polystyrene microspheres by a simple coating approach. We investigated the compatibility, coating ratio, and fire performance of EPS- and MDI-coated EPS foam using a water-based intumescent flame retardant system. The microscopic study revealed that the water-based intumescent flame retardant materials were successfully incorporated with and without MDI-coated EPS microspheres. The cone calorimeter tests (CCTs) of the MDI-coated EPS containing water-based intumescent flame retardant materials exhibited better flame retardant performance with a lower total heat release (THR) 7.3 MJ/m2, peak heat release rate (PHRR) 57.6 kW/m2, fire growth rate (FIGRA) 2027.067 W/m2.s, and total smoke production (TSP) 0.133 m2. Our results demonstrated that the MDI-coated EPS containing water-based intumescent flame retardant materials achieved flame retarding properties as per fire safety standards.
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Jacob, Leena, Abhilash Tv, and Shajan Abraham. "FORMULATION AND EVALUATION OF PERINDOPRIL MICROENCAPSULES BY USING DIFFERENT POLYMER." Asian Journal of Pharmaceutical and Clinical Research 10, no. 2 (2017): 153. http://dx.doi.org/10.22159/ajpcr.2017.v10i2.14899.
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Objective: The study was carried out with an objective to achieve a potential sustained release oral drug delivery system of an antihypertensive drug, Perindopril which is a ACE inhibitor having half life of 2 hours. Perindopril is water soluble drug, so we can control or delay the release rate of drug by using release retarding polymers. This may also decrease the toxic side effects by preventing the high initial concentration in the blood.Method: Microcapsules were prepared by solvent evaporation technique using Eudragit L100 and Ethyl cellulose as a retarding agent to control the release rate and magnesium stearate as an inert dispersing carrier to decrease the interfacial tension between lipophilic and hydrophilic phase. Results: Prepared microcapsules were evaluated for the particle size, percentage yield, drug entrapment efficiency, flow property and in vitro drug release for 12 h. Results indicated that the percentage yield, mean particle size, drug entrapment efficiency and the micrometric properties of the microcapsules was influenced by various drug: polymer ratio. The release rate of microcapsules could be controlled as desired by adjusting the combination ratio of dispersing agents to retarding agents.Conclusion:Perindopril microcapsules can be successfully designed to develop sustained drug delivery, that reduces the dosing frequency and their by one can increase the patient compliance.
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Bhusara, Hiral S., Ara T. Patel, and Mayuree D. Patel. "Development of gastroretentiv floating tablets of losartan potassium by sublimation method." International Journal of Pharmaceutical Chemistry and Analysis 8, no. 2 (2021): 66–74. http://dx.doi.org/10.18231/j.ijpca.2021.014.
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The purpose of present study was to formulate and Evaluate Sustained release floating tablet of losartan Potassium using Camphor and Polyethylene Oxide as Pore formation for floating and release retarding agent respectively to improve gastric residence time and patient compliance in management of hypertension. The tablet was prepared by direct compression by using HPMC K4 as dry binder. Camphor and PEO as floating and release retarding agent for sustained release floating tablet. Post compression was done to increase the hardness and floating time of tablet. Release modifier was used to speed up the release of drug from sustained release floating tablet. The effect of two independent variables like amount of Sublimating agent (camphor) and amount of Polyethylene oxide (PEO) on Q30min, Q360min, and Q720min was optimized using 32 factorial design and analyzed using the software design expert 10.0.3. The observed (actual values) responses were coincided well with the predicted values, given by the optimization technique. The floating tablet were characterized by FTIR for drug excipient compatibility.
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Wang, Yachao, and Jiangping Zhao. "Ecological Ammonium Thiocyanate-Modified Geopolymeric Coating for Flame-Retarding Plywood." Coatings 9, no. 8 (2019): 479. http://dx.doi.org/10.3390/coatings9080479.
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An ecological ammonium thiocyanate (NH4SCN)-modified geopolymeric coating was facilely prepared for flame-retarding plywood. The effect of NH4SCN on the flame resistance was preliminarily investigated using cone calorimeter (CC), scanning electron microscope (SEM), X-ray diffraction (XRD), and thermal gravimetry (TG). The results show that 1 wt.% NH4SCN as dopant is of paramount importance to generate a compact and continuous coating. The formation of a smooth, intact, and uniform-swelling siliceous layer during combustion facilitates enhanced fire resistance, evidenced by the increased fire performance index (FPI), reduced fire growth index (FGI), and 39.7% decreased value of peak heat release rate (pHRR), in comparison to those of the sample without NH4SCN. Because of the reducibility of O2-consuming NH4SCN, the compact shielding-layer containing carbonate and sulfate, as well as the release of NH3, the NH4SCN-modified geopolymeric coating exerts an enhancement on the flame-retardant efficiency.
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Simran, Tanwar, Tikariya Komal, and Sharma Vimukta. "Formulation and Evaluation of Sustained Release Matrix Tablet of Nimesulide Using Pomegranate Peel and Acacia." International Journal of Pharmaceutical Sciences and Medicine 7, no. 7 (2022): 11–24. http://dx.doi.org/10.47760/ijpsm.2022.v07i07.002.
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The main objective of the study is the formulation and evaluation of sustained release matrix tablet of Nimesulide using pomegranate peel and acacia as natural polymer. The preformulation study of Nimesulide was conducted and λmax was found at 300 nm. The sustained release matrix tablet was prepared using Pomegranate peel as Release rate retardant, Acacia as polymer, Polyvinylpyrrolidone K30 as Binder, Isopropyl alcohol as Granulation solution, Micro Crystalline Cellulose as Diluent, Magnesium stearate as Lubricant and Talc as Glidant. Several formulations were prepared by taking different drug concentration in Pomegranate peel (Release rate retardant) with varying ratio of binder to lubricants. Various formulations of sustained release matrix tablet of Nimesulide F1, F2, F3, F4, F5, F6 was prepared. The prepared granules were evaluated for different parameters like Bulk density, Tapped density, Angle of repose, Carr’s index, Hausner’s ratio which shows the excellent flow properties of formulation. The physical characteristic of Nimesulide sustained release matrix tablets (F1 to F6) such as thickness, diameter, hardness, friability, weight variation and drug content were determined and results of the formulations (F1 to F6) found to be within the limits specified in official books. The drug content of all the formulation were found to be in the range of 99.59 to 99.83 % w/w, which is within the specified limit as per Indian Pharmacopoeia 1996 (i.e. 90-110% w/w). The drug released from formulation F1 to F3 was found to be 93.7, 92.9 and 92.2 % for Nimesulide respectively. The drug released from formulation F4 to F6 was found to be 94.1, 93.9 and 92.8% for Nimesulide respectively. The release rate of F1 and F4 was found to be higher when compared to other formulations this is due to increase in the concentration of polymer. These results are indicating that has higher drug retarding ability for long duration. All the formulations were analyzed for stability testing. All the formulations from F1 to F6 were found to be stable.
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Cheng, Bing-Ming, J. R. Grover, E. A. Walters, and J. T. Clay. "Kinetic energy release distributions from dissociative photoionization of weakly bound trimers at 14–27 eV." Physical Chemistry Chemical Physics 20, no. 32 (2018): 21034–42. http://dx.doi.org/10.1039/c8cp03013h.
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Lü, Shaoyu, Chunmei Gao, Xinggang Wang, et al. "Synthesis of a starch derivative and its application in fertilizer for slow nutrient release and water-holding." RSC Adv. 4, no. 93 (2014): 51208–14. http://dx.doi.org/10.1039/c4ra06006g.
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Gholap, Apoorv Nitin, Dr Pranav Parekh, Dr Mrunal Shirsat, Vaibhav Narwade, and Gokul Mali. "Formulation and Evaluation of Sustained Release Matrix Tablet of Quinapril by Using Natural Polymers." International Journal for Research in Applied Science and Engineering Technology 13, no. 4 (2025): 5533–42. https://doi.org/10.22214/ijraset.2025.69586.
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Abstract: In present investigation an attempt has been made to design and develop some Quinapril matrix tablets using KarayaGum, Guar gum, KollidonSRas release retarding polymers. Quinapril is Anti-hypertensive drug which lowers blood pressure level and has been selected to prepare sustained release dosage forms. Quinapril sustained release matrix tablets were prepared using KarayaGum, Guar gum, KollidonSR as base polymer by wet granulation method. FTIR spectral analysis showed that characteristic peak of Quinapril pure drug was retained in the spectra of all the formulations indicating the intactness of the drug in all the formulations. Quinapril matrix tablets formulated employing Kollidon SR and combination of Karaya Gum and Guar gum provided slow and controlled release of Quinapril up to 24 hr. All the tablet formulation showed compliance with pharmacopoeia standard as the time increases. The dissolution result shows that an increased amount of polymer resulted in reduced drug release. A concentration dependent drug release is evident in case of the polymer i.e., lower concentration of polymers, release is marginally retarded at higher concentration is considerable. Prepared sustained formulation containing KarayaGum, Guar gum, KollidonSR as release retarding polymers (F6) probably showing better release based up to 98% drug release within 24 hours.
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Karim, Samira, Mohiuddin Ahmed Bhuiyan, and Md Sohel Rana. "Formulation and in vitro Evaluation of Glimepiride Sustained Release Tablets: Comparison with Immediate Release Tablets." Bangladesh Pharmaceutical Journal 18, no. 2 (2015): 157–62. http://dx.doi.org/10.3329/bpj.v18i2.24315.
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This work aims at the design of a sustained release formulation of glimepiride which is currently available in the treatment of type 2 diabetes mellitus and to investigate the effect of polymers on the release profile of glimepiride. Glimepiride sustained release tablets were prepared by direct compression method using different ratios of various release retarding polymers such as carbopol, ethyl cellulose, methocel K4 MCR, methocel K15 MCR, methocel K100 MCR and xanthum gum. These formulations were also compared with glimepiride immediate release tablets. The prepared tablets were subjected to various physical parameter tests including weight variation, friability, hardness, thickness, diameter, etc. In vitro dissolution studies of the formulations were done at pH 6.8 in phosphate buffer using USP apparatus 2 (paddle method) at 50 rpm. The percent releases of all the formulations (30) were 73.11%- 98.76% after 8 hours. The release pattern followed zero order kinetics and the release of the drug was hindered by the polymers used in the study. On the other hand, 100% drug was released within 1 hour from the immediate release tablet of glimepiride. The study reveals that the polymers used have the capacity to retard the release of the drug from the sustained release tablets and the more is the amount of the polymer in the formulation the less is the release of drug showing more retardation of drug release.Bangladesh Pharmaceutical Journal 18(2): 157-162, 2015
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G., Mahesh *. "FORMULATION DEVELOPMENT AND EVALUATION OF MATRIX TABLETS OF PROPRANOLOL HCL BY USING RELEASE RETARDING AGENTS." Journal of Pharma Research 7, no. 3 (2018): 31–36. https://doi.org/10.5281/zenodo.1209341.
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<strong><em>ABSTRACT</em></strong> <strong><em>T</em></strong><em>he main aim of the present work is to formulate and develop matrix tablets of Propranolol HCl. Selected suitable method for preparation process of Direct compression method for matrix tablets of Propranolol HCl by using varying concentrations of HPMC K4M, HPMC K100M, sodium alginate and Xanthan gum as a release retarding agents, dibasic calcium phosphate, Microcrystalline cellulose as diluents, talc and magnesium stearate as glidant and lubricant. Excipients compatibility studies were carried out by Stability studies and FT-IR studies between API and selected excipients. All the matrix tablets of Propranolol HCl formulations were evaluated for Pre-compression and post-compression parameters. All the formulations were evaluated for the hardness, friability, thickness, weight variation, drug content uniformity, and in-vitro drug release studies. Based on in-vitro drug release the polymer Xanthan gum showed better dissolution control compared to the other polymers like HPMC K4M and HPMC K100M and sodium alginate. Release of Propranolol HCl from the tablets formulated by employing 25mg of Xanthan gum and 77 mg dibasic calcium phosphate showed that more drug release So, the formulation F- 10 was the optimized formula.</em> <strong><em>KEYWORDS</em></strong><em>: Propranolol HCl, HPMC, Sodium Alginate, Xanthangum, Dibasic Calcium Phosphate, Release Retarding agents, Diluents, Glidant, Release Kinetics.</em>
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Chen, Jiayi, Yansong Liu, Jiayue Zhang, Yuanlin Ren, and Xiaohui Liu. "Synthesis of Novel Arginine-Based Flame Retardant and Its Application in Lyocell Fabric." Molecules 26, no. 12 (2021): 3588. http://dx.doi.org/10.3390/molecules26123588.
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Lyocell fabrics are widely applied in textiles, however, its high flammability increases the risk of fire. Therefore, to resolve the issue, a novel biomass-based flame retardant with phosphorus and nitrogen elements was designed and synthesized by the reaction of arginine with phosphoric acid and urea. It was then grafted onto the lyocell fabric by a dip-dry-cure technique to prepare durable flame-retardant lyocell fabric (FR-lyocell). X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR) analysis demonstrated that the flame retardant was successfully introduced into the lyocell sample. Thermogravimetric (TG) and Raman analyses confirmed that the modified lyocell fabric featured excellent thermal stability and significantly increased char residue. Vertical combustion results indicated that FR-lyocell before and after washing formed a complete and dense char layer. Thermogravimetric Fourier-transform infrared (TG-FTIR) analysis suggested that incombustible substances (such as H2O and CO2) were produced and played a significant fire retarding role in the gas phase. The cone calorimeter test corroborated that the peak of heat release rate (PHRR) and total heat release (THR) declined by 89.4% and 56.4%, respectively. These results indicated that the flame retardancy of the lyocell fabric was observably ameliorated.
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Dou, Yanli, Aixun Ju, Zheng Zhong, Yutong Huo, and Weiguo Yao. "Flame-Retardant and Transparent Unsaturated Polyester Based on P/N Liquid Flame Retardants and Modified Halloysite Nanotubes." Materials 17, no. 3 (2024): 761. http://dx.doi.org/10.3390/ma17030761.
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Unsaturated polyester resin (UPR) with excellent flame retardant is mainly obtained by adding large amounts of flame retardants, usually at the expense of mechanical properties. In this work, a reactive flame retardant containing phosphorus and nitrogen (DOPO-N) was successfully synthesized and incorporated in UPR as a crosslinker. The mechanical and flame-retardant properties of UPR composites were enhanced. UPR/30DOPO-N passed a UL-94 V-1 rating with a limiting oxygen index (LOI) of 30.8%. The tensile strength of UPR/30DOPO-N increased by 24.4%. On this basis, a small amount of modified HNTs (VHNTs) was added to further improve the flame-retardant properties of the composite. With the introduction of 3 wt% VHNTs, the composite passed the UL-94 V-0 rating. The peak of heat release rate (PHRR) and total heat release (THR) of it decreased by 60.7% and 48.3%, respectively. Moreover, the detailed flame-retarding mechanism of DOPO-N and VHNTs was investigated by thermogravimetric infrared spectroscopy (TG-IR), Raman spectra, and X-ray photoelectron spectroscopy (XPS). It was found that DOPO-N played a role in quenching the flame in the gas phase and cooperated with VHNTs to enhance the barrier effect in the condensed phase.
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Lam, Matthew, Nour Nashed, and Ali Nokhodchi. "Liqui-Mass Technology as a Novel Tool to Produce Sustained Release Liqui-Tablet Made from Liqui-Pellets." Pharmaceutics 13, no. 7 (2021): 1049. http://dx.doi.org/10.3390/pharmaceutics13071049.
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The Liqui-Mass technology (also known as Liqui-Pellet technology) has shown promising results in terms of enhancing the drug release rate of water insoluble drugs in a simplistic approach. However, there is no current study on sustained-release formulation using the Liqui-Mass technology. In this study, an attempt was made to produce a sustained-release Liqui-Tablet for the first time using a matrix-based approach. The non-volatile co-solvent used in the investigation included Tween 80, Tween 20 and Kolliphor EL. The production of sustained-release propranolol hydrochloride Liqui-Tablet was successful, and data from the saturation solubility test and dissolution test did not show much difference among the mentioned non-volatile co-solvent. The best Liqui-Tablet formulation took 24 h for drug release to reach at around 100%. There seemed to be a synergistic retarding drug release effect when a non-volatile co-solvent and Eudragit RS PO were used together. The increase of Eudragit RS PO concentration increased the retardant effect. Kinetic drug release analysis suggests that the best formulation followed the Higuchi model. The flowability of pre-compressed Liqui-Tablet pellets had no issues and its size distribution was narrow. Liqui-Tablet was generally robust and most formulations passed the friability test. The study revealed that Liqui-Mass technology can be employed to sustain drug release.
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Muzib, Y. Indira, K. Swetha, and YR Ambedkar. "Study on Natural Gums and Resins as Release Retarding Agents in Development of Sustained Release Matrix Tablets of Didanosine." INTERNATIONAL JOURNAL OF DRUG DELIVERY TECHNOLOGY 14, no. 02 (2024): 619–24. http://dx.doi.org/10.25258/ijddt.14.2.01.
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Didanosine is an anti-retroviral drug which helpful in preventing human immunodeficiency virus (HIV) from multiplication in the body. This drug has a relatively short half-life and low absolute bioavailability and requires frequent dosing. So to avoid this frequent dosing and to improve the patient’s compliance, the development of sustained-release tablets is necessary. Natural gums and resins play an important role in retarding drug release. Didanosine extended-release matrix formulations developed with wet granulation using gum kondagogu, guar gum, gum olibanum, and olibanum resin, and evaluated for pre and post-compression parameters. The outcome of all evaluation tests is reached IP specifications. Formulations with kondagogu F1-F3 failed to extend the drug release. F4-F6 was formulated with gum kondagogu and guar gum, in which F4 prolonged the release up to 12 hours with 98.23%. The formulations F7 with olibanum resin release 96.13%, and F10 with gum olibanum releases 93.15% drug at the end of 12 hours. The conclusion from the study was that natural polymers could be used to enhance drug release for an extended period.
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Poornima, P* Abbulu K. Mukkanti K. "DESIGN AND EVALUATION OF GASTRORETENTIVE NIFEDIPINE FLOATING TABLETS IN THE TREATMENT OF HYPERTENSION." Indo American Journal of Pharmaceutical Sciences 04, no. 11 (2017): 4178–89. https://doi.org/10.5281/zenodo.1048997.
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Gastro retentive floating tablets of Nifedipine were prepared using various grades of HPMC as a release retarding agent. Nifedipine is a dihydropyridine derivative effectively used in the management of various cardiovascular diseases in long term therapy, the biological half life is only 2 hours. The main aim of the present study is to prolong the drug release upto 24 hours. The tablets were prepared by direct compression method and the formulations were evaluated different physic chemical and dissolution studies. The formulations from each polymer F6, F10 and F20 gave better controlled drug release and floating properties in comparison to the other formulations. HPMC K 250 PH PRM, HPMC K 750 PH PRM and HPMC K 1500 PH PRM were used in different ratios to check the release retarding mechanism and duration. Among all the formulation F10 was selected as optimized formulation because it showed maximum drug release FTIR studies results revealed that there was no incompatibility between drug and excipients. The optimized formulation was best fitted in Zero Order and Korsmeyer-Peppas. Nifedipine floating tablets can be an innovative and promising approach for the delivery of Nifedipine for the treatment of hypertension (high blood pressure) and angina (chest pain) for prolonged period of time. Keywords: Nifedipine, Floating tablets, Hypertension, HPMC, Floating lag time.
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Tomiak, Florian, Melanie Zitzmann, and Dietmar Drummer. "A Multi-Material Flame-Retarding System Based on Expandable Graphite for Glass-Fiber-Reinforced PA6." Polymers 15, no. 20 (2023): 4100. http://dx.doi.org/10.3390/polym15204100.
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A synergistic multi-material flame retardant system based on expandable graphite (EG), aluminum diethylphosphinate (AlPi), melamine polyphosphate (MPP), and montmorillonite (MMT) has been studied in glass-fiber-reinforced polyamide 6 (PA6). Analytical evaluations and fire performances were evaluated using coupled thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR) as well as cone calorimetry, UL-94 fire testing, and limiting oxygen index (LOI). A combination of EG/AlPi/MPP/MMT has been shown to provide superior flame-retarding properties when integrated at 20 wt.% into glass-fiber-reinforced PA6 (25 wt.%), achieving UL-94 V0 classification and an oxygen index of 32%. Strong residue formation resulted in low heat development overall, with a peak heat release rate (pHRR) of 103 kW/m2, a maximum of average heat release rate (MAHRE) of 33 kW/m2, and deficient total smoke production (TSP) of 3.8 m2. Particularly remarkable was the structural stability of the char residue. The char residue could easily withstand an areal weight of 35 g/cm2, showing no visible deformation.
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Kabir, Abul Kalam Lutful, Shimul Halder, and Abu Shara Shamsur Rouf. "In vitro Release Kinetic Study of Theophylline from Kollidon SR Polymer Based Matrix Tablet." Dhaka University Journal of Pharmaceutical Sciences 14, no. 1 (2015): 43–48. http://dx.doi.org/10.3329/dujps.v14i1.23734.
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Controlled release tablet matrix of theophylline was prepared with kollidon SR, a spray dried powder grade polymer (polyvinyl acetate and povidone based matrix rate retarding hydrophobic materials) by utilizing direct compression technique. Different proportion of kollidon SR was used to develop the matrix builder in the five proposed formulations (F-1 to F-5) for the study of release rate retardant effect at 10, 12, 15, 18 and 21% of total weight of matrix tablet, respectively. The in vitro dissolution study of the matrices of those proposed tablet formulations were carried out in simulated gastric medium (pH 1.3) for first two hours and then in simulated intestinal medium (pH 6.8) for 6 hours using USP dissolution apparatus II (paddle method). The formulation F-3 (using 15% polymer) and F-4 (using 18 % polymer) met the optimum release profiles of active ingredient for 8 hr period of total study. The release kinetics for theophylline was plotted against zero order, first order and Higuchi release rate kinetics to evaluate the release mechanism of drug from the formulated tablet matrix. The release kinetics of formulation F-3 and F-4 was followed very closely by Higuchi release rate kinetic order than other kinetics such as zero order and first order kinetics which has been reflected the type of drug release from the tablet matrix by diffusion as well as erosion mechanism.Dhaka Univ. J. Pharm. Sci. 14(1): 43-48, 2015 (June)
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Taghizadeh Davoudi, Ehsan, Mohamed Ibrahim Noordin, Ali Kadivar, Behnam Kamalidehghan, Abdoreza Soleimani Farjam, and Hamid Akbari Javar. "Preparation and Characterization of a Gastric Floating Dosage Form of Capecitabine." BioMed Research International 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/495319.
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Gastrointestinal disturbances, such as nausea and vomiting, are considered amongst the main adverse effects associated with oral anticancer drugs due to their fast release in the gastrointestinal tract (GIT). Sustained release formulations with proper release profiles can overcome some side effects of conventional formulations. The current study was designed to prepare sustained release tablets of Capecitabine, which is approved by the Food and Drug Administration (FDA) for the treatment of advanced breast cancer, using hydroxypropyl methylcellulose (HPMC), carbomer934P, sodium alginate, and sodium bicarbonate. Tablets were prepared using the wet granulation method and characterized such that floating lag time, total floating time, hardness, friability, drug content, weight uniformity, andin vitrodrug release were investigated. The sustained release tablets showed good hardness and passed the friability test. The tablets’ floating lag time was determined to be 30–200 seconds, and it floated more than 24 hours and released the drug for 24 hours. Then, the stability test was done and compared with the initial samples. In conclusion, by adjusting the right ratios of the excipients including release-retarding gel-forming polymers like HPMC K4M, Na alginate, carbomer934P, and sodium bicarbonate, sustained release Capecitabine floating tablet was formulated.
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Qin, Zuo Dong, G. J. Duns, Zhang Lin, and Ji Shuang Chen. "Flame Retardant Properties of Fiber-Based Decorative Wallboard." Advanced Materials Research 487 (March 2012): 739–47. http://dx.doi.org/10.4028/www.scientific.net/amr.487.739.
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In this study, bamboo pulp is utilized as the main raw material for the production of compression-molded, fiber-based decorative wallboard panels which have three-dimensional geometric structure and possess environmentally compatible “green” flame retardant properties. The effectiveness of several flame retarding agents, including the Al(OH)3 single component system, the Al(OH)3/Mg(OH)2 mixed system and the Al(OH)3/Mg(OH)2/Zinc Borate mixed system are examined in terms of the resulting flame resistance, physical properties and oxygen indexes of the fiber-based decorative wallboard. The results show that the Al(OH)3/Mg(OH)2/Zinc Borate multicomponent mixed system is the most ideal flame retardant system for such applications. Results indicate that the optimal formulation consist of: 30% Mg(OH)2/25% Al(OH)2 /15% Zinc borate (relative mass ratio). Under such conditions, the oxygen index of the fiber decorates wallboard is 34.4, and the level of formaldehyde release reaches a value of E0.
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Wang, Yun, Weiwen Ge, Zhigui Ma, et al. "Use of mesoporous polydopamine nanoparticles as a stable drug-release system alleviates inflammation in knee osteoarthritis." APL Bioengineering 6, no. 2 (2022): 026101. http://dx.doi.org/10.1063/5.0088447.
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Osteoarthritis drugs are often short-acting; therefore, to enhance their efficacy, long-term, stable-release, drug-delivery systems are urgently needed. Mesoporous polydopamine (MPDA), a natural nanoparticle with excellent biocompatibility and a high loading capacity, synthesized via a self-aggregation-based method, is frequently used in tumor photothermal therapy. Here, we evaluated its efficiency as a sustained and controlled-release drug carrier and investigated its effectiveness in retarding drug clearance. To this end, we used MPDA as a controlled-release vector to design a drug-loaded microsphere system (RCGD423@MPDA) for osteoarthritis treatment, and thereafter, tested the efficacy of the system in a rat model of osteoarthritis. The results indicated that at an intermediate drug-loading dose, MPDA showed high drug retention. Furthermore, the microsphere system maintained controlled drug release for over 28 days. Our in vitro experiments also showed that drug delivery using this microsphere system inhibited apoptosis-related cartilage degeneration, whereas MPDA-only administration did not show obvious cartilage degradation improvement effect. Results from an in vivo osteoarthritis model also confirmed that drug delivery via this microsphere system inhibited cartilage damage and proteoglycan loss more effectively than the non-vectored drug treatment. These findings suggest that MPDA may be effective as a controlled-release carrier for inhibiting the overall progression of osteoarthritis. Moreover, they provide insights into the selection of drug-clearance retarding vectors, highlighting the applicability of MPDA in this regard.
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J. Singhavi, Dilesh. "DUAL RELEASE CHRONOTHERAPEUTIC SYSTEM OF POORLY WATER SOLUBLE ANTIHYPERTENSIVE DRUG CARVEDILOL: DESIGN, DEVELOPMENT AND IN VITRO CHARACTERIZATION." Indian Drugs 60, no. 04 (2023): 24–30. http://dx.doi.org/10.53879/id.60.04.12851.
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The current research investigation’s goal was to design a core-in-cup type pulsatile system of an antihypertensive drug (carvedilol phosphate) to reduce the evening and early-morning symptoms of hypertension. An inclusion complex of this drug was prepared with hydroxyl propyl beta cyclodextrin to increase carvedilol solubility. Using direct compression method, various batches of core tablets were formulated using Croscarmellose sodium as a superdisintegrant. Core tablets of the optimized formulation were press coated with backing layer and release-retarding plug layer. An in vitro release research was performed after evaluating the physicochemical characteristics of the core in cup design tablets. Based on the lag time of 8 h between the first and second pulse releases, a batch containing sodium alginate (100 mg) and hydroxypropyl methylcellulose K4M (100 mg) was chosen as the optimum batch. Thus, the dual-release core-in-cup pulsatile tablets may be utilized for managing the hypertension symptoms appearing in chronological order.
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Rai, Aastha, Rajeev Kumar Malviya, Dhanraj Patidar, Krati Sharma, and Vishnu Raj. "Formulation Development and Evaluation of Gastroretentive Delivery System (Microspheres) Using Natural Polymer." Journal of Drug Delivery and Therapeutics 9, no. 4 (2019): 496–503. http://dx.doi.org/10.22270/jddt.v9i4.3079.
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Microspheres are novel drug delivery approach to control release of pharmacologically active ingredient as per patient need. Natural polymers like fenugreek mucilage are cheap, biodegradable and have been proved safe for pharmaceutical formulation. Higher loading efficiency was observed for all the formulations and also the drug release was observed for the period of 12 hours. Thus, the simvastatin microsphere using fenugreek mucilage showed promising results in retarding the drug release. It can be concluded from whole study that due to the formation of polymeric network system or other active moiety can be easily entrapped with the matrix and hydration and swelling of natural polymer controlled their release pattern
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Pasa, Gourishyam, Prasanta Kumar Choudhury, and Ghanshyam Panigrahi. "FORMULATION DESIGN AND OPTIMIZATION OF ORAL FLOATING MATRIX TABLETS OF CIPROFLOXACIN HCL BY USING HPMC AND XANTHAN GUM WITH EXPERIMENTAL DESIGN." Asian Journal of Pharmaceutical Research and Development 6, no. 6 (2018): 23–35. http://dx.doi.org/10.22270/ajprd.v6i6.430.
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The oral floating matrix tablets of Ciprofloxacin Hydrochloride were formulated by Experimental design by using HPMC K100M and Xanthan gum as the retardant polymers each with three different levels with an approach to increase gastric residence and thereby improve drug bioavailability. From FTIR results confirm the absence of chemical interaction between the drug with the excipients used in tablet formulations. Also, there was no shift in the endotherm of in the drug- excipients mixtures indicating compatibility of drug with all the excipients. All the tablets were prepared by effervescent approach in which Sodium bicarbonate was added as a gas generating agent. Floating Matrix tablets were prepared by direct compression method and prepared tablets were evaluated for weight variation, percentage friability, hardness and drug content studies. All the formulations showed compliance with pharmacopeia standards. Floating lag times of all the formulations were within 1 minute and Total floating time of all the formulations were more than 12 hours. In vitro release studies revealed that the release rate decreased with increase polymer proportion of retarding polymers. The formulation CHX8 sustained release of drug for 12 hrs with 20% release of drug after 1hr and more than 97% at the end of 12 hrs. From the Kinetic model it was found that the optimized formulation CHX8 showed linearity in case of Zero order (R2: 0.952) and Higuchi model (R2: 0.948). By fitting data to Korsmeyer-Peppas model and ‘n’ value lying above 0.5 indicating non Fickian release.
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Islam, Muhammad Rashedul, Md Elias Al Mamun, Md Mizanur Rahman Moghal, and Md Habibur Rahman. "Development and Evaluation of Indomethacin Controlled Release Press Coated Tablets." Dhaka University Journal of Pharmaceutical Sciences 14, no. 2 (2016): 187–92. http://dx.doi.org/10.3329/dujps.v14i2.28509.
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In the present work, several batches of indomethacin press coated tablets were prepared with drug and Avicel PH 102 utilizing the press coating technology. The core tablet was compression coated with minimal compression pressure. The compression coating mixture was formulated using various amount of lactose and xanthan gum which was used as the release retarding agent. Three formulations (IX-1, IX-2 and IX-3) were designed to evaluate the release profile as function of xanthan gum load. In vitro drug release testing demonstrated that the drug release was inversely proportional to the amount of xanthan gum in the coating formulations. In addition, formulation IX-2 was modified by incorporating hydroxypropyl methyl cellulose (HPMC) 15 cps into the compression coating formulation to understand their effects on drug release. The formulation was evaluated for its properties and correlated with in vitro and kinetic release studies. Incorporation of HPMC caused the highest fraction of drug to be released in the dissolution fluid. The physico-chemical properties of the excipients can be held responsible for the discrepancy in release rate of indomethacin. From kinetic analysis drug release was found to follow Higuchi mechanism for all the formulations. Overall, the study concluded that excipients present in the coating formulations make a significant impact on drug release.Dhaka Univ. J. Pharm. Sci. 14(2): 187-192, 2015 (December)
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Dr., G. Nagaraju, Teena Lavdya, Sirisha V., and Hareesh Dara Dr. "FORMULATION AND EVALUATION OF RATE RETARDING POLYMERS IN THE PROLONGED RELEASE TABLETS OF LOVASTATIN." Journal of Pharma Research 13, no. 06 (2024): 82–89. https://doi.org/10.5281/zenodo.14243508.
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<strong>Abstract</strong> <strong>T</strong>he aim of the present study was to develop Lovastatin extended release tablets to maintain constant therapeutic levels of the drug for over 12hrs. Gum Acacia, Almond gum and Grewia gum were used as polymers. All the formulations were passed various physic chemical evaluation parameters such as bulk density, tapped density, cars index, hausners ratio, angle of repose , weight variation, hardness, thickness, friability and drug content. From the dissolution studies it was evident that the formulation F9 showed better and desired drug release pattern i.e., 98.82% in12 hours. It contains the Grewia gumas polymer. It followed Higuchi release kinetics mechanism. Keywords: Lovastatin, Gum Acacia, Almond gum, Grewia gum and Extended Release Tablets.
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Ren, Xiu Bin, An Ning Zhou, Bo Liu, and Long Lei. "Preparation and Retarding Characteristics of Coal/Mg,Al-Hydrotalcite Composites." Advanced Materials Research 179-180 (January 2011): 270–73. http://dx.doi.org/10.4028/www.scientific.net/amr.179-180.270.
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Coal/Mg,Al-hydrotalcite composites were prepared and the flame-retardant properties were studied. DSC analysis was used to study the flame-retardant properties of the composites. The results showed that the heat release of coal can be effectively decreased and the ignition point of the coal can be availably increased. The results indicated that coal/Mg,Al-hydrotalcite composites showed excellent flame-retardant performance.
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Yang, Man, and Bihe Yuan. "Modification of Aluminum Hydroxide by Ball Milling: A Feasible Method to Obtain High-Efficiency Flame Retardants for Production of High-Performance EVA Composites." Materials 18, no. 5 (2025): 984. https://doi.org/10.3390/ma18050984.
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Aluminum hydroxide (ATH) is an environmentally friendly flame retardant widely employed in polymers. However, the high loading of ATH, due to its limited efficiency, potentially compromises other properties, including mechanical properties. This work explores a feasible ball milling strategy for high-efficiency ATH-based flame retardants (PPA-ATH and PPOA-ATH), fabricated by employing phenylphosphinic acid (PPA) and phenylphosphonic acid (PPOA) as surface modifiers and water as the processing solvent. The characterization study of PPA-ATH and PPOA-ATH demonstrates that ball milling effectively reduces their particle size, enhances their specific surface area, and improves their dispersibility within the ethylene-vinyl acetate (EVA) matrix. PPOA-ATH exhibited superior capabilities in enhancing the thermal stability and flame retardancy of EVA composites compared to PPA-ATH. The incorporation of PPOA-ATH resulted in the retarding in the temperature at 50% mass loss by 21 °C and an increase in the char residue of 34.5% at 700 °C. Furthermore, PPOA incorporation led to reductions of 81.0% in the peak heat release rate, 48.1% in the total heat release, 73.7% in the peak smoke production rate, and 41.2% in the total smoke production compared to neat EVA. This green modification strategy successfully addresses the application limitations of ATH, providing a feasible and environmentally friendly method for high-efficiency ATH-based flame retardant fabrication.
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Srikanth Meka, Venkata, Chew Ee Li, and Ravi Sheshala. "Design and statistical optimization of an effervescent floating drug delivery system of theophylline using response surface methodology." Acta Pharmaceutica 66, no. 1 (2016): 35–51. http://dx.doi.org/10.1515/acph-2016-0002.
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Abstract The aim of this research was to formulate effervescent floating drug delivery systems of theophylline using different release retarding polymers such as ethyl cellulose, Eudragit® L100, xanthan gum and polyethylene oxide (PEO) N12K. Sodium bicarbonate was used as a gas generating agent. Direct compression was used to formulate floating tablets and the tablets were evaluated for their physicochemical and dissolution characteristics. PEO based formulations produced better drug release properties than other formulations. Hence, it was further optimized by central composite design. Further subjects of research were the effect of formulation variables on floating lag time and the percentage of drug released at the seventh hour (D7h). The optimum quantities of PEO and sodium bicarbonate, which had the highest desirability close to 1.0, were chosen as the statistically optimized formulation. No interaction was found between theophylline and PEO by Fourier Transformation Infrared spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) studies.
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Kim, Mee-Kyung, Seung-Yong Seong, Ju-Young Seoh, et al. "Orientia tsutsugamushi Inhibits Apoptosis of Macrophages by Retarding Intracellular Calcium Release." Infection and Immunity 70, no. 8 (2002): 4692–96. http://dx.doi.org/10.1128/iai.70.8.4692-4696.2002.
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ABSTRACT Orientia tsutsugamushi shows both pro- and antiapoptotic activities in infected vertebrate cells. Apoptosis of THP-1 cells induced by beauvericin was inhibited by O. tsutsugamushi infection. Beauvericin-induced calcium redistribution was significantly reduced and retarded in cells infected with O. tsutsugamushi. Antiapoptotic activities of O. tsutsugamushi in infected cells are most probably due to inhibition of the increase in the cytosolic calcium concentration.
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Wang, Feiyue, Jiahao Liao, Long Yan, and Mengtao Cai. "Facile Construction of Polypyrrole Microencapsulated Melamine-Coated Ammonium Polyphosphate to Simultaneously Reduce Flammability and Smoke Release of Epoxy Resin." Polymers 14, no. 12 (2022): 2375. http://dx.doi.org/10.3390/polym14122375.
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A unique mono-component intumescent flame retardant, named PPy-MAPP, of which melamine-coated ammonium polyphosphate (MAPP) was microencapsulated by polypyrrole (PPy), was synthesized and carefully characterized. The obtained PPy-MAPP was applied to epoxy resin (EP) for obtaining flame-retarded EP composites. The results show that PPy-MAPP imparts better flame retardancy and smoke suppression properties to EP compared to the same addition of MAPP. The EP composite with 15 wt% PPy-MAPP easily passes the UL94 V-0 rating and achieves an LOI value of 42.4%, accompanied by a 61.9% reduction in total heat release (THR) and a 73.9% reduction in total smoke production (TSP) when compared with pure EP. The char residue analysis shows that PPy-MAPP can promote a generation of more phosphorus-rich structures in the condensed phase that improve the integrity and intumescence of char against fire. The mechanical test indicates that PPy-MAPP has a less negative effect on the tensile strength and elastic modulus of epoxy resin due to the good compatibility between PPy-MAPP and the EP matrix, as supported by differential scanning calorimetry (DSC) analyses. In this paper, these attractive features of PPy-MAPP provide a new strategy to prepare satisfactory flame retardant and super flame retarding EP composites.
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Hadzieva, Jasmina, Marija Glavas-Dodov, Maja Simonoska-Crcarevska, et al. "Tablets of soy protein-alginate microparticles with Lactobacillus casei 01: Physicochemical and biopharmaceutical properties." Chemical Industry and Chemical Engineering Quarterly 25, no. 1 (2019): 57–66. http://dx.doi.org/10.2298/ciceq170616019h.
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The aim of the study was to develop direct-compress-tablets of microencapsulated probiotic Lactobacillus casei 01 in soy protein-alginate microparticles and excipients able to provide probiotic delivery near the colon. Considering their physicochemical properties, all series of tablets prepared met the requirements of the Ph Eur 9.0. The compaction of the probiotic loaded microparticles caused viability decrease up to 1.5 log cycles. The tablets containing Methocel K100M showed higher potential for preserving probiotic viability in simulated gastrointestinal fluids within 4 h and retarding its release in the intestinal stage, maintaining the required minimum of viable probiotic cells above 107 CFU per gram of tablet. In addition, acceptable storage stability (viability of probiotic above 106 CFU/g) at 25?C/60% relative humidity for 42 days was observed. In conclusion, novel tablet dosage forms of microencapsulated L. casei 01 were prepared with high potential for preserving probiotic viability in simulated gastrointestinal fluids and retarding its release in the lower intestine. Further research is needed to optimize the formulation and process parameters in order to obtain tablets with probiotic viability over long storage periods.
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Siddiqui, Mehak, L. K. Omray, and Pushpendra Soni. "Formulation of Metformin Sustained Release Tablet Using Natural Polymer." Journal of Drug Delivery and Therapeutics 11, no. 2 (2021): 31–37. http://dx.doi.org/10.22270/jddt.v11i2.4579.
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The overall objective of the present work was to develop an oral sustained-release (SR) Metformin tablet that is prepared by the direct compression method by using hydrophilic hydroxyl propyl methyl cellulose (HPMC) and Guar gum polymer alone as well as in combination at different concentrations. Metformin is a biguanide that has a relatively short plasma half-life. It has low absolute bioavailability. All the properties were evaluated for thickness, weight variation, hardness and drug content uniformity and in vitro drug release. The mean dissolution time is used to characterize the drug release rate from a dosage form that indicates the drug release-retarding efficiency of the polymer. The hydrophilic matrix of HPMC alone could not control the Metformin release effectively for 12 h but when combined with Guar gum, it could slow down the release of drug and, thus, can be successfully employed for formulating Sustain Release matrix tablets.
 Keywords: Guar gum, hydroxylpropylmethylcellulose, matrix tablets, release kinetics,
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IC, Giri, and Ramanunny AK. "Impact of Particle Size of Acyclovir Loaded Mucoadhesive Microcapsules on Drug Release Characteristics." INTERNATIONAL JOURNAL OF DRUG DELIVERY TECHNOLOGY 14, no. 04 (2024): 1077–89. https://doi.org/10.25258/ijddt.14.4.23.
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This study focuses on the preparation and evaluation of prolonged-release acyclovir (ACV)-loaded mucoadhesive microcapsules using the emulsion solvent evaporation technique with sodium CMC as a mucoadhesive and rate-retarding polymer. The microcapsules exhibited a high yield (92.67–97.85%), drug entrapment efficiency (72.79–92.17%), and mucoadhesion (62–73%). Particle size ranged between 250 μm (F1) and 302 μm (F4), increasing with polymer concentration. In vitro drug release studies conducted in pH 1.2 phosphate buffer revealed an inverse relationship between polymer concentration and release rate. Smaller microcapsules (F1) demonstrated faster drug release (95% in 12 hours), while larger microcapsules (F4) showed sustained release (55% in 12 hours). These insights underscore the importance of optimizing particle size to achieve desired therapeutic outcomes. This study provides valuable data for the development of tailored microcapsule formulations, improving the efficacy and compliance of ACV therapy.
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Dileep, Kumar Awasthi, B. Puranik Sangamesh, Saraswat Rohit, Kumar Jhajharia Mahesh, and Sharma Prashant. "Design, Formulation Development and Evaluation of Matrix Tablet Containing Labetalol HCL." International Journal of Engineering Research & Science 6, no. 8 (2020): 05–14. https://doi.org/10.5281/zenodo.4090901.
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<strong>Abstract</strong><strong>—</strong> The objective of present work was to design and develop sustained release matrix tablets of anti-hypertensive drug Labetalol hydrochloride. Hydroxypropyl methyl cellulose K15, Sodium CMC, Xanthan gum and Tamarind seed polysaccharide used as a rate retarding polymer. Whereas Polyvinyl Pyrrolidone and Microcrystalline cellulose are used as granulating agent and diluent. The influence of variable concentration of polymers on the release rate of drug was investigated. The results of the present work point out that the rate of Labetalol hydrochloride release from polymers like Hydroxypropyl methyl cellulose K15, Sodium CMC, Xanthan gum and Tamarind seed polysaccharide are mainly controlled by the drug–polymer ratio. The prepared sustained release matrix tablets were evaluated for various parameters like hardness, friability, uniformity of weight, uniformity of drug content and in vitro drug release studies.
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Vijay, R. Chakote* Mrunal K. Shirsat Deepak A. Joshi Mayuri M. Ban Gunesh N. Dhembre. "DESIGN AND DEVELOPMENT OF MATRIX TABLET OF LABETALOL HCL BY USING TAMARIND SEED POLYSACCHARIDE AS POLYMER." INDO AMERICAN JOURNAL OF PHARMACEUTICAL SCIENCES 05, no. 02 (2018): 805–14. https://doi.org/10.5281/zenodo.1174319.
Full textAbstract:
The objective of present work was to design and develop sustained release matrix tablets of anti-hypertensive drug Labetalol hydrochloride. Hydroxypropyl methyl cellulose K15, Sodium CMC, Xanthan gum and Tamarind seed polysaccharide used as a rate retarding polymer. Whereas Polyvinyl Pyrrolidone and Microcrystalline cellulose are used as granulating agent and diluent. The influence of variable concentration of polymers on the release rate of drug was investigated. The results of the present work point out that the rate of Labetalol hydrochloride release from polymers like Hydroxypropyl methyl cellulose K15, Sodium CMC, Xanthan gum and Tamarind seed polysaccharide are mainly controlled by the drug–polymer ratio. The prepared sustained release matrix tablets were evaluated for various parameters like hardness, friability, uniformity of weight, uniformity of drug content and in vitro drug release studies. Keywords: Hydroxypropyl methyl cellulose K15, Sodium CMC, Xanthan gum and Tamarind seed polysaccharide, Sustained-release, Labetalol hydrochloride Formulation.
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Soumya, B., Swarupa Arvapalli, J. V. C. Sharma, and Potnuri Nagaraju. "Design, Characterization and In-vitro Evaluation of Superporous Hydrogel Tablets of Nimodipine." Journal of Drug Delivery and Therapeutics 9, no. 3 (2019): 300–309. http://dx.doi.org/10.22270/jddt.v9i3.2659.
Full textAbstract:
The present work was aimed to formulate Superporous Hydrogel tablets of Nimodipine using an effervescent approach for gastro retentive drug delivery system to improve its bioavailability by using different rate retarding polymers like plantago ovata, tamarind gum and carbopol, along with suitable excipients. All the formulations were prepared by direct compressionmethod. The prepared tablets of all the formulations were evaluated for physical characteristics, in‐vitro drug release, hardness and friability. Optimized formulation F8 containing 0.3% of plantago ovata and carbopol each was considered as the best formulation with respect to in vitro drug release for 12 hours release action. The results showed that the drug release rate was decreased as the viscosity of the polymer was increased. The drug release kinetics was performed for the optimized formulation and it shows zero orderwith non-fickian transport drug release. Keywords: Superporous Hydrogel tablets, Nimodipine, plantago ovata, tamarind gum and carbopol, non-fickian transport drug release.
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Wei, An, Shunxiang Wang, Yongjin Zou, Cuili Xiang, Fen Xu, and Lixian Sun. "Preparation of a Flame-Retardant Curing Agent Based on Phytic Acid–Melamine Ion Crosslinking and Its Application in Wood Coatings." Polymers 16, no. 11 (2024): 1557. http://dx.doi.org/10.3390/polym16111557.
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To broaden the applications of wood, it is necessary to prepare flame-retardant coatings that can protect wood substrates during combustion. In this study, a bio-based, intumescent, flame-retardant phytic acid–melamine polyelectrolyte (PM) was prepared using phosphorus-rich biomass phytic acid and nitrogen-rich melamine as raw materials through an ion crosslinking reaction. Subsequently, a series of bio-based, flame-retardant wood coatings were prepared by optimizing the structure of urea–formaldehyde resin with the addition of melamine, sodium lignosulfonate, and PM as a flame-retardant curing agent. Woods coated with PM-containing coatings displayed significantly improved flame-retardant performances in comparison to uncoated woods. For PM-cured woods, the measured values of total heat release and total smoke production were 91.51% and 57.80% lower, respectively, compared with those of uncoated wood. Furthermore, the fire growth index decreased by 97.32%, indicating a lower fire hazard. This increase in flame retardancy and smoke suppression performance is due to the dense expanded carbon layer formed during the combustion of the coating, which isolates oxygen and heat. In addition, the mechanical properties of the flame-retardant coatings cured with PM are similar to those cured with a commercial curing agent, NH4Cl. In addition, the prepared flame-retardant coating can also stain the wood. This study proves the excellent flame-retarding and curing effect of ammonium phytate in urea–formaldehyde resin coatings and provides a new approach for the application of bio-based flame retardants in wood coatings.
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Penabaka VenugopalaiahPenabaka Venugopalaiah, KP Benidicts Prem Prakash, Yerikala Ramesh, and M Alagusundaram. "Formulation and evaluation of extended-release tablets of trimetazidine HCL." World Journal of Advanced Research and Reviews 18, no. 3 (2023): 993–1002. http://dx.doi.org/10.30574/wjarr.2023.18.3.1003.
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The present study was undertaken with an aim to formulate develop and evaluate Trimetazidine HCL extended release matrix tablets using different polymers as release retarding agent. Pre formulation study was done initially and results directed for the further course of formulation. Based on Pre formulation studies different batches of Trimetazidine HCL were prepared using selected excipients. Powders were evaluated for tests Angle of repose, Bulk density, tapped density, compressibility index, and Hausner ratio before being punched as tablets. It was concluded that the tablets of batch F9 had considerable swelling behaviors and in vitro drug release. Percentage drug release in 8 hr is 80.77. It was observed that tablets of batch F9 followed the Huguchi release profiles. From the results and discussion it is concluded that formulation of Extended release matrix tablet of HCL containing HPMC K-15 (19.44%) and Hyper mellose (19.44%), Ethyl cellulose (19.44%) batch F9 can be taken as an ideal or optimized formulation Extended release matrix tablet for 8 hour release as it fulfills the requirements for extended release matrix tablet.
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Penabaka, Venugopalaiah, Benidicts Prem Prakash KP, Ramesh Yerikala, and Alagusundaram M. "Formulation and evaluation of extended-release tablets of trimetazidine HCL." World Journal of Advanced Research and Reviews 18, no. 3 (2023): 993–1002. https://doi.org/10.5281/zenodo.8434813.
Full textAbstract:
The present study was undertaken with an aim to formulate develop and evaluate Trimetazidine HCL extended release matrix tablets using different polymers as release retarding agent. Pre formulation study was done initially and results directed for the further course of formulation. Based on Pre formulation studies different batches of Trimetazidine HCL were prepared using selected excipients. Powders were evaluated for tests Angle of repose, Bulk density, tapped density, compressibility index, and Hausner ratio before being punched as tablets. It was concluded that the tablets of batch F9 had considerable swelling behaviors and in vitro drug release. Percentage drug release in 8 hr is 80.77. It was observed that tablets of batch F9 followed the Huguchi release profiles. From the results and discussion it is concluded that formulation of Extended release matrix tablet of HCL containing HPMC K-15 (19.44%) and Hyper mellose (19.44%), Ethyl cellulose (19.44%) batch F9 can be taken as an ideal or optimized formulation Extended release matrix tablet for 8 hour release as it fulfills the requirements for extended release matrix tablet.
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Chandani, Rajak* Meenakshi Kandwal Shivanand Patil. "Preparation And Evaluation Of Non-Effervescent Gastro-Retentive Tablets For Controlled Rlease Of Pregabalin." International Journal in Pharmaceutical Sciences 2, no. 9 (2024): 825–36. https://doi.org/10.5281/zenodo.13770648.
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In the pharmaceutical field, the development and assessment of non-effervescent tablets are essential for ensuring the controlled release of active ingredients such as Pregabalin. Non-effervescent tablets are specifically designed to release medication gradually and consistently over an extended period, which is particularly advantageous for drugs like Pregabalin utilizing HPMC K100M and Carbopol 971P as release-retarding polymers. The objective of this study was to create and assess controlled release matrix tablets containing Pregabalin. The tablets were produced through wet granulation and assessed for different parameters like angle of repose, bulk density, true density, compressibility index, Hausner ratio and evaluation of various physical and chemical properties like- swelling characteristics, in vitro buoyancy, adhesion retention, and in vitro drug release, drug content. The optimized formulation exhibited the desired drug release profile and was determined to be comparable to the product Lyrica CR. Stability tests performed on the optimized formulation demonstrated that it remained physically and chemically stable under both accelerated and real-time storage conditions.
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Karmarkar, R. R., M. P. Wagh, S. R. Baviskar, S. H. Patil, and S. K. Khawshe. "FORMULATION DEVELOPMENT OF MATRIX TABLET OF STAVUDINE BY USING CARBOXY METHYL TAMARIND KERNEL POWDER AS A NOVEL DRUG RELEASE RETARDING AGENT." INDIAN DRUGS 52, no. 04 (2015): 28–36. http://dx.doi.org/10.53879/id.52.04.10235.
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The aim of the present study was to evaluate carboxy methyl tamarind kernal powder as a novel drug release retarding agent. To evaluate the same, sustained release matrix tablets of stavudine were prepared by using HPMC K4M and carboxy methyl tamarind kernal powder, by using a direct compression technique. The formulations were prepared by using different drug: polymer ratios into formulations such as F1 to F9. The compressed tablets were evaluated for thickness, hardness, friability, drug content and in vitro dissolution rates. Formulation F6, having a hardness of 5.46 ± 0.25, showed the desired release profile for a period of 24 h in simulated intestinal fluids (pH 7.4). Kinetic data treatment indicated that the release of stavudine from the matrix tablet follows coupling of diffusion and erosion mechanisms. The study proves that the optimized sustained release tablet is capable of releasing the drug in a sustained manner for 24 h.
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A, Vanjari, Chauhan M, Newadkar P, and Nikam A. "Development and Optimization of Nateglinide Loaded Polymeric Sustained Release Microspheres." INTERNATIONAL JOURNAL OF DRUG DELIVERY TECHNOLOGY 14, no. 04 (2024): 1124–29. https://doi.org/10.25258/ijddt.14.4.52.
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This research study aims to develop and characterize of polymeric sustained release microspheres of Nateglinide (NTG), anti-diabetic drug known for its shorter half-life, which leads to poor bioavailability and frequent dosing. NTG polymeric microsphere developed by Emulsion-Solvent Diffusion-Evaporation method. Ethyl cellulose was used as rate retarding material. The polymeric microsphere were characterised for % yield, encapsulation efficiency, drug release, FTIR, and SEM. The developed NTG polymeric microspheres were smooth and spherical with porous nature and showed entrapment efficiency in range of 59.43% - 88.47 % with highest percent yield of 98.75%. FTIR spectra showed drug excipient compatibility while optimized formulation F5 showed complete drug release up to 24 hrs. These results indicate that NTG microspheres offer a safe and effective drug delivery system with prolonged release, which can enhance bioavailability, improve patient compliance, and reduce dosing frequency.
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Mukhopadhyay, Soumen, Tathagata Roy, and Tapan Kumar Chatterjee. "Formulation Development and Evaluation of Diacerein Loaded Microsphere by Spray Coating (Wurster Method)." Journal of Drug Delivery and Therapeutics 9, no. 4 (2019): 454–60. http://dx.doi.org/10.22270/jddt.v9i4.3082.
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Diacerein loaded microspheres were prepared by spray coating(wurster method) using hydroxyl propyl methyl cellulose (HPMC) and ethyl cellulose as release retarding polymer with a view to manufacture sustained release drug delivery. Drug content in the microspheres was determined by HPLC assay followed by drug entrapment efficiency. Shape and Surface topography of Diacerein loaded microspheres was determined by scanning electron microscopy. Fourier transform infrared spectroscopy (.FT-IR), X-ray diffraction Spectroscopy (XRD), and Differential scanning calorimetry (DSC) studies were done to establish drug polymer and other excipients compatibility and stability. Sustained release action was established by In-vitro release study. The result shows that Diacerein loaded microsphere using hydroxyl propyl methyl cellulose and ethyl cellulose polymer can be a new addition in the field of pain management for the treatment of osteoarthritis. Keywords: Microsphere, Diacerein, HPMC, Ethyl cellulose, Spray coating.
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B., Ranjith Kumar* Santhosh Illendula P. Shyam Sundar G. Guna Sheela Nadimenti Mogulaiah. "DEVELOPMENT OF MULTIPARTICULATE SYSTEM OF MEBEVERINE HYDROCHLORIDE FOR THE TREATMENT OF IRRITABLE BOWEL SYNDROME." INDO AMERICAN JOURNAL OF PHARMACEUTICAL SCIENCES 05, no. 02 (2018): 1013–19. https://doi.org/10.5281/zenodo.1183928.
Full textAbstract:
Pellets were witnessed as one of the promising modified drug delivery systems widely employed now-a-days in the management of various diseases. Mebeverine hydrochloride pellets were coated by suspension layer technique using fluidized bed processor (FBP). This method applied found to be effective to coat the drug uniformly onto the non-pareil (NP) seeds. In this study, three coatings viz., binder (PVP K30), barrier (EC 5 cps) and sustained release (EC 3 cps and HPMC 10 cps) were applied. At each stage of coating, optimized formulation was found out for next subsequent coating and they were F4, B1 and S3. F4 is a formulation with binder solution 2.5% w/v concentration showed 90% coating efficiency with less processing problems and less lump formation. To this formulation barrier coating was given with EC 5 cps. Barrier pellets coated with rate retarding polymers EC 3 cps and HPMC 10 cps. Out of three formulations S3 formulation exhibited 90.39% drug release at 16th hr which matched with the 90.69% release of marketed formulation. Similarity (f2) and dissimilarity (f1) factors for S3 were 83.5 and 6.2 respectively. This revealed the S3 is in vitro bioequivalent with marketed formulation. These pellets were evaluated further for micromeritic properties, SEM and dissolution rate test studies. The micrometrics of S3 revealed good flow ability for packing and filling into capsules (Compressibility index, angle of repose and hausner’s ratio were 24.29%, 26.04° and 1.009 respectively). The formulation was extended for stability studies at different conditions. The stability data produced evidenced the formulation was intact during storage. Key words: pellets, suspension layering technique, rate retarding polymers.
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Hussain, Atif, Véronic Landry, Pierre Blanchet, Doan-Trang Hoang, and Christian Dagenais. "Fire Performance of Intumescent Waterborne Coatings with Encapsulated APP for Wood Constructions." Coatings 11, no. 11 (2021): 1272. http://dx.doi.org/10.3390/coatings11111272.
Full textAbstract:
In this work, intumescent coatings were prepared for protection of wood from fire. The fire-retardant chemical ammonium polyphosphate (APP) is known to have poor resistance to water and high humidity as it is hygroscopic in nature. To improve the water resistance, durability and fire resistance of the intumescent coating, APP was modified using a hybrid organic-inorganic polysiloxane encapsulation shell prepared by the sol–gel method. The physical and chemical properties of the intumescent mix containing microencapsulated ammonium polyphosphate (EAPP) particles were characterized by X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), water absorption, dynamic vapor sorption (DVS) and thermogravimetric analysis (TGA). The EAPP mix showed 50% reduction in water absorption, 75% reduction in water vapor sorption and increased thermal stability when compared to the APP mix. The intumescent coatings were applied on wood samples, and their fire performance was evaluated using a cone calorimeter test. The intumescent coatings containing EAPP mix showed better fire retarding properties with longer time to ignition, lower heat release rate and shorter heat release peak when compared to the coating without EAPP mix. The prepared intumescent coating shows higher resistance to water and moisture, and it has great potential to be used in bio-based construction industry for enhancing the fire resistance of wood.
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Zhang, Lingping, Marie Wahlgren, and Björn Bergenståhl. "Oil-Based Delivery Control Release System Targeted to the Later Part of the Gastrointestinal Tract—A Mechanistic Study." Pharmaceutics 14, no. 5 (2022): 896. http://dx.doi.org/10.3390/pharmaceutics14050896.
Full textAbstract:
Oil-based drug delivery systems have been studied in different aspects. The present study proposes a new application for an oil-based delivery system, focusing on controlled release until the drug reaches the later part of the small intestine. Bulk surfactants and interfacial surfactants were added into the oil formulation to provide a better mechanistic understating of the lipolysis. Validation of the modified in vitro method shows the overall conversion from medium-chain triglyceride oil (MCT oil) to free fatty acids (FFA) of 100 ± 4% in five replicates. This fully converted level and high reproducibility are fundamental for the following investigations where any retarding effect can be distinguished from the experimental errors. The results show that viscosity and thermodynamic activity have limited retardation. Furthermore, the former may change the kinetics of lipolysis, while the latter changes the equilibrium level. The gel-forming retarder (ethylcellulose) displayed a strong effect. Whereas the lipolysis was significantly retarded (>50%) when the retarders altered the interfacial composition (poloxamer 407), degradable interfacial surfactants did not have the same effect. However, surface-active, lipolysis-resistant retarders with a high CMC did not show a retarding effect.
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Agho, O., and A. Okunlola. "Design and Preliminary Characterization of Sweet Potato Starch – Urea-Borate Polymer." Nigerian Journal of Pharmaceutical Research 20, no. 1 (2024): 1–9. http://dx.doi.org/10.4314/njpr.v20i1.1.
Full textAbstract:
Background – Sweet potato (Ipomoea batatas) starch has been reported for its potential as a directly compressible and sustained- release polymer in its native and modified forms. Chemical modification by crosslinking with urea and borax to form starch urea-borate will enhance its drug release-retarding properties. Objective – To design starch-urea-borate (SUB) polymer using sweet potato starch to produce a new, affordable biodegradable polymer, and carry out preliminary characterization of the polymer. Method – Native starch was extracted from sweet potato tubers and crosslinked with urea and borax to form starchurea borate (SUB) polymer. The native and modified starches were characterized for morphology (SEM), FT-IR, DSC, pH, densities, swelling, flow properties and viscosity. Results – Modification yielded 96.66% w/w of SUB and disrupted the granular structure of the native starch, producing significantly larger (p<0.01) granules with irregular shapes. FTIR spectrum revealed a peak at 3369.05 cm1 due to –NH2 confirming the presence of a secondary amide resulting from the polymerization reaction between urea and starch in the presence of borate. A shift in the peak of DSC endotherm was observed for SUB. Modification yielded lower particle density but higher bulk and tapped densities. The swelling index increased significantly (p<0.01). Hausner’s ratio (1.06± 0.00), Carr’s index (6.33± 0.01%) and angle of repose (26.14±1.15º) showed good flow but reduction in compressibility of SUB. Viscosity revealed shear thickening or dilatant behaviour. Conclusion- The material and physicochemical properties of SUB polymer showed its potential for application in drug delivery systems, possibly as a release retarding polymer.
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P, Poornima, Abbulu K, and Mukkanti K. "Design and Preclinical Evaluation of Gastroretentive Floating Tablets of Quetiapine Fumerate." International Journal of Pharmaceutical Sciences and Nanotechnology 11, no. 3 (2018): 4122–28. http://dx.doi.org/10.37285/ijpsn.2018.11.3.6.
Full textAbstract:
The present study was focused on gastro-retentive tablets of quetiapine fumarate using hydrophilic polymers HPMC K250 PH PRM, HPMC K750 PH PRM and HPMC K1500 PH PRM as release retarding agents. WSR 301 was chosen as resin, sodium bicarbonate was used as effervescent agents. FTIR studies revealed that there is no interaction between the drug and polymers used for the formulation. The tablets were prepared by direct compression method and the release rate was found to decrease with proportional increase in the ratio of polymer to drug. Quetiapine fumarate is absorbed well from stomach and therefore is a very good drug to be formulated into gastro retentive floating dosage form. In-vitro release profile of quetiapine fumarate and marketed product when compared, the optimized formulation F19 showed drug release of 98.65% within 24 h whereas 96.78% of the drug was released from the marketed product within 1h. The optimized formulation remained stable when subjected to accelerated stability studies. In vivo radiographic studies of quetiapine fumarate optimized formulation (F19) supported the expectations in prolonging the gastric residence time in the fasted state in beagle dogs. Cmax and AUC values of optimized formulation were found to be significantly higher than of marketed product. In conclusion, gastro-retention can be a promising approach to enhance bioavailability of quetiapine fumarate with narrow absorption window in upper GIT.