Journal articles: 'Thin layer chromatography (TLC)'

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Katayama, Yoshiki, and Shino Manabe. "Thin-layer chromatography（TLC）." Drug Delivery System 35, no. 2 (March 25, 2020): 147–49. http://dx.doi.org/10.2745/dds.35.147.

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Verbitski, Sheryl M., Gerald T. Gourdin, Larissa M. Ikenouye, James D. McChesney, and Jana Hildreth. "Detection of Actaea racemosa Adulteration by Thin-Layer Chromatography and Combined Thin-Layer Chromatography-Bioluminescence." Journal of AOAC INTERNATIONAL 91, no. 2 (March 1, 2008): 268–75. http://dx.doi.org/10.1093/jaoac/91.2.268.

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Abstract Actaea racemosa L. (black cohosh; syn. Cimicifuga racemosa L. Nutt.) is a native North American perennial whose root and rhizome preparations are commercially available as phytomedicines and dietary supplements, primarily for management of menopausal symptoms. Despite its wide use, methods that accurately identify processed A. racemosa are not well established; product adulteration remains a concern. Because of its similar appearance and growing locales, A. racemosa has been unintentionally mixed with other species of the genus, such as Actaea pachypoda Ell. (white cohosh) and more commonly Actaea podocarpa DC. (yellow cohosh). The genus Actaea also has 23 temperate species with numerous common names, which can also contribute to the misidentification of plant material. Consequently, a variety of Actaea spp. are common adulterants of commercially available black cohosh preparations. Thin-layer chromatography (TLC) and combined TLC-bioluminescence (Bioluminex) are efficient, economical, and effective techniques which provide characteristic patterns and toxicity profiles for each plant species. These data indicate that common black cohosh adulterants, such as yellow cohosh, can be differentiated from black cohosh by TLC and TLC-bioluminescence. This study also showed that unknown contaminants that were not detected using standard A. racemosa identity techniques were readily detected by TLC and TLC-bioluminescence.

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Renger, Bernd. "Contemporary Thin-Layer Chromatography in Pharmaceutical Quality Control." Journal of AOAC INTERNATIONAL 81, no. 2 (March 1, 1998): 333–40. http://dx.doi.org/10.1093/jaoac/81.2.333.

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abstract The progress in layers, instrumentation, and the development of automated scanning densitometers have led to a remarkable improvement of the features of thin-layer chromatography (TLC) and especially its high performance version (HPTLC). Contemporary TLC or HPTLC combines the techniques' inherent advantages which include high sample throughput, simultaneous processing of standards and samples, flexibility, easy postchro matographic visualization techniques, and the ability to handle complex or crude samples with minimum sample cleanup—with improved selectivity, sensitivity, and accuracy. It is a very economical chromatographic technique that competes with and complements HPLC. Development and validation of procedures can be performed rapidly in full accordance with all current international guidelines.

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Sherma, Joseph. "Recent Advances in Thin-Layer Chromatography of Pesticides." Journal of AOAC INTERNATIONAL 82, no. 1 (January 1, 1999): 48–54. http://dx.doi.org/10.1093/jaoac/82.1.48.

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Abstract Advances in the use of thin-layer chromatography (TLC) and high-performance TLC (HPTLC) for separation, detection, and qualitative and quantitative determination of pesticides, other agrochemicals, and related compounds are reviewed for the period 1996–1998. Analyses are covered for avariety of food, biological, and environmental samples and for residues of various pesticides, including insecticides, herbicides, and fungicides, belonging to different chemical classes. References on formulation analysis, hydrophobicity studies, and use of TLC and thin-layer radiochromatography for studies of pesticide metabolism, degradation, uptake, and related studies also are included.

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Braselton, W. Emmett, and Malgorzata Johnson. "Thin Layer Chromatography Convulsant Screen Extended by Gas Chromatography-Mass Spectrometry." Journal of Veterinary Diagnostic Investigation 15, no. 1 (January 2003): 42–45. http://dx.doi.org/10.1177/104063870301500109.

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Acute onset convulsive disorders in the canine may result from exposure to a variety of toxicants including strychnine, insecticides, metaldehyde, zinc phosphide, methylxanthines, drugs of abuse, bromethalin, and the tremorgenic mycotoxins (roquefortine and penitrem A). Although several of the above can be identified in a single gas chromatography-mass spectrometry (GC-MS) screen most have to be determined by separate tests. This report describes a modification of the strychnine extraction procedure, which allows thin layer chromatographic (TLC) identification of strychnine, bromethalin, roquefortine, and penitrem A in suspect baits, stomach contents or vomitus, and extends the identification to a wide variety of drugs, pesticides, and environmental contaminants by GC-MS. Samples were mixed with base, extracted into CH2Cl2 and the organic fraction back-extracted with acid. The organic fraction (neutrals) was purified by gel permeation chromatography (GPC) and analyzed by TLC to determine penitrem A and bromethalin. The acidic aqueous fraction was adjusted to pH > 9 and extracted into CH2Cl2. The resulting CH2Cl2 layer (bases) was then analyzed by TLC to determine strychnine and roquefortine. The organic basic and neutral fractions were recombined with a late eluting GPC fraction and analyzed by GC-MS. Of 312 samples analyzed by TLC from 1995 to 2001, 35 were positive for strychnine alone, 58 were positive for both roquefortine and penitrem A, 4 were positive for roquefortine alone, and 1 was positive for bromethalin. None of the samples were positive for penitrem A alone. Samples negative by TLC were analyzed by the GC-MS extended procedure since mid-1999, and 14 have shown positive for a wide variety of compounds with convulsant activity.

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Komsta, Łukasz. "Chemometrics in Fingerprinting by Means of Thin Layer Chromatography." Chromatography Research International 2012 (November 28, 2012): 1–5. http://dx.doi.org/10.1155/2012/893246.

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The paper is written as an introductory review, presenting summary of current knowledge about chemometric fingerprinting in the context of TLC, due to a rather small interest in the literature about joining TLC and chemometrics. The paper shortly covers the most important aspects of the chemometric fingerprinting in general, creating the TLC fingerprints, denoising, baseline removal, warping/registering, and chemometric processing itself. References being good candidates as a starting point are given for each topic and processing step.

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Sherma, Joseph. "Recent Advances in Thin-Layer Chromatography of Pesticides." Journal of AOAC INTERNATIONAL 84, no. 4 (July 1, 2001): 993–1000. http://dx.doi.org/10.1093/jaoac/84.4.993.

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Abstract Advances in the applications of thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) for the separation, detection, and qualitative and quantitative determination of pesticides, other agrochemicals, and related compounds are reviewed for the period 1998–2000. Analyses are covered for a variety of samples, such as food, biological, and environmental, and for residues of pesticides of various types, including insecticides, herbicides, and fungicides, belonging to different chemical classes. References on formulation analysis, hydrophobicity studies, and the use of TLC and thin-layer radiochromatography (TLRC) for studies of pesticide metabolism, degradation, uptake, and related studies are also included.

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Huang, Du Shu, Yun Hui Long, Yong Hong, Jing Wang, Na Wu, and Jie Wu. "Chiral Resolution of Ofloxacin Using Carboxylated Multi-Walled Carbon Nanotubes Mediated Thin-Layer Chromatography." Materials Science Forum 809-810 (December 2014): 128–30. http://dx.doi.org/10.4028/www.scientific.net/msf.809-810.128.

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To resolute chiral ofloxacin, we demonstrated a new method of using carboxylated multi-walled carbon nanotubes (MWCNTs) impregnated thin-lay chromatography (TLC). The relative RF value of carboxylated MWCNTs impregnated TLC was 31.3. A general discussion that focuses on the possibility of functionalized MWCNTs in the field of chromatographic chiral resolution is presented.

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Ilbeigi, Vahideh, and Mahmoud Tabrizchi. "Thin Layer Chromatography-Ion Mobility Spectrometry (TLC-IMS)." Analytical Chemistry 87, no. 1 (December 9, 2014): 464–69. http://dx.doi.org/10.1021/ac502685m.

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Mohammad, Ali, Abdul Moheman, and Gaber El-Desoky. "Amino acid and vitamin determinations by TLC/HPTLC: review of the current state." Open Chemistry 10, no. 3 (June 1, 2012): 731–50. http://dx.doi.org/10.2478/s11532-012-0019-0.

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AbstractSeveral methods to determine amino acids and vitamins in biological and pharmaceutical samples have been reported. Thin layer chromatography (TLC) finds its place when the relatively costly equipment required by other methods is unavailable. This review covers the 1991–2010 literature on TLC/HPTLC (high performance thin layer chromatography) amino acid and vitamin determinations. It gives an overview of the special features as well as the problems in TLC/HPTLC determinations of amino acids and vitamins. Various chromatographic systems useful in amino acid and vitamin identification, separation and quantitation of are presented in tabular form. Future prospects of TLC/HPTLC for amino acid and vitamin determinations are also discussed.

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Du Toit, Elsa S., Ilona Von Maltzahn, and Puffy Soundy. "Chemical Analysis of Cultivated Hypoxis hemerocallidea using Thin Layer Chromatography." HortScience 40, no. 4 (July 2005): 1119B—1119. http://dx.doi.org/10.21273/hortsci.40.4.1119b.

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Hypoxis hemerocallidea (African potato) is in high demand as a medicinal plant and therefore it is becoming scarce in its natural habitat. Thus, the objective of this study was to investigate the effect of cultivation practices on the active ingredients of the corm over a 12-month period. Different TLC (Thin Layer Chromatography) methods were also investigated when separating the different compounds. Plants were grown under a tunnel in plastic bags containing bark or sand growing media. The planted corms were treated with different fertigation frequencies and harvesting took place during four seasons. The harvested material was sliced, freeze-dried, and ground into a fine powder. Different solvents, namely methanol, acetone, and chloroform (chosen for their polarity) were used to extract the compounds from the ground material. The extracted residues were redissolved and spotted as thin streaks onto TLC plates. The TLC plates were then developed in different solvents and sprayed with different chemicals to bring out the different compounds found in the plant extract. Results on the TLC plates indicated that the amount of residue extracted with different solvents were significantly different. Therefore, TLC methods need to be considered when separating the different compounds. The growing media affected the amount of compounds produced from the corms during the 12-month period. The harvest season also played a role in the amount of active ingredients produced during the year. Therefore, cultivation practices influence the occurrence of active ingredients of H. hemerocallidea.

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Henderson, M. J. "Thin-layer chromatography of free porphyrins for diagnosis of porphyria." Clinical Chemistry 35, no. 6 (June 1, 1989): 1043–44. http://dx.doi.org/10.1093/clinchem/35.6.1043.

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Abstract In this simple thin-layer chromatographic (TLC) technique for evaluating porphyrin excretion, porphyrins are extracted from urine or feces, then separated on silica-gel TLC plates. The distinct porphyrin bands are observed by viewing the plates under long-wave fluorescent light. Positive screening tests can readily be confirmed or rejected, and a more comprehensive investigation confidently undertaken.

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Hofstraat, J. W., C. Gooijer, and N. H. Velthorst. "The Combination of High-Resolution Molecular Fluorescence Spectroscopy with Liquid Chromatography and Thin-Layer Chromatography." Applied Spectroscopy 42, no. 4 (May 1988): 614–19. http://dx.doi.org/10.1366/0003702884429229.

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Under certain conditions, highly specific fluorescence spectra, showing molecular vibrations as in infrared spectroscopy, can be obtained for the analysis of compounds separated in TLC and microbore LC. Two techniques, both employing low-temperature solid samples, are available: Shpol'skii spectroscopy and Fluorescence Line-Narrowing (FLN) spectroscopy. The former utilizes n-alkane solvents, which form regular, crystalline solids; the latter is based on selective laser excitation. Both techniques can be applied for detection in TLC. FLN is more feasible, since the Shpol'skii method requires spraying of the TLC plate, which leads to significant spreading of the spots. FLN can also be used for offline detection in micro-LC after immobilization of the column effluent on a TLC plate. In addition, some exploratory experiments on the applicability of FLN for on-column detection in LC are presented.

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Nicola, Anthony J., Arkady I. Gusev, and David M. Hercules. "Direct Quantitative Analysis from Thin-Layer Chromatography Plates Using Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry." Applied Spectroscopy 50, no. 12 (December 1996): 1479–82. http://dx.doi.org/10.1366/0003702963904458.

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Direct quantitative analysis using thin-layer chromatography (TLC) coupled with matrix-assisted laser desorption/ionization mass spectrometry (MALDI) has been demonstrated. An internal standard and a data collection protocol were used for analysis directly from TLC plates to compensate for shot-to-shot signal degradation, as well as deviations of analyte and internal standard spatial distributions within the TLC spot. Cocaine hydrochloride was used as a model compound for this study, and cocaine- d3 was used as the internal standard. Quantitative analysis by TLC/MALDI yielded comparable results to those obtained with stainless steel substrates (the standard MALDI method) for point-to-point repeatability, % RSD of the standard curve, and measurement precision. For silica gel and reverse-phase TLC plates, the relative standard deviation of the standard curve slope was better than 3%, the relative standard deviations of the analyte/internal standard intensity ratios ranged from 3.8% to 9.5%, the precision was estimated to be better than 12%, and the detection limits were estimated to be 60 pg for both TLC plate types. Quantitative analysis using stainless steel substrates yielded a lower detection limit than that obtained by TLC/MALDI by a factor of six. Perspectives for improving the detection limits of direct TLC/MALDI quantitative analysis are discussed. Index Headings: MALDI; TLC; Quantification.

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Moschidis, Michael C. "Notizen: Isolation of Beef Brain Phosphonolipids by Thin Layer Chromatography: Their Identification and Silicic Acid Column Chromatographic Separation." Zeitschrift für Naturforschung C 41, no. 3 (March 1, 1986): 369–74. http://dx.doi.org/10.1515/znc-1986-0323.

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The isolation and identification of the phosphonolipids from beef brain - right lobe, left lobe and cerebellum - is herein reported. The phosphonolipids were isolated by preparative thin layer chromatography (TLC) using the solvent system methanol/water (2:1, v/v) and identified preliminarily by TLC. The isolated phosphonolipids were subjected to silicic acid column chromatographic separation and the thus separated phosphonolipids were identified by TLC, nitrogen-phosphorus determinations and IR spectroscopy.

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Chong, K. P., J. W. Mansfield, M. H. Bennet, and J. F. Rossiter. "Detection of antifungal compounds in Arabidopsis thaliana and brassica oleracea by thin layer chromatography ." ASEAN Journal on Science and Technology for Development 23, no. 1&2 (October 30, 2017): 123. http://dx.doi.org/10.29037/ajstd.99.

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Thin Layer Chromatography (TLC) was applied to detect antifungal compounds both in Arabidopsis thaliana and Brassica oleracea after elicited by various biotic and abiotic elicitors.From TLC bioassays the only strong zone of inhibition detected after challenged by Pseudomonas syringae pv.maculicola was from Arabidopsis tissue and later confirmed by spectrophotometry as camalexin but no corresponding phytoalexin was found in broccoli leaf.

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Sherma, Joseph. "Recent Advances in the Thin-Layer Chromatography of Pesticides: A Review." Journal of AOAC INTERNATIONAL 86, no. 3 (May 1, 2003): 602–11. http://dx.doi.org/10.1093/jaoac/86.3.602.

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Abstract Advances in the applications of thin-layer chroma-tography (TLC) and high-performance TLC for the separation, detection, identification, and determination of pesticides, other agrochemicals, and related compounds are reviewed for the period 2000–2002. Analyses are described for a variety of samples, such as food, biological, and environmental samples, and for residues of pesticides of various types, including insecticides, herbicides, and fungicides, belonging to different chemical classes. References are included for residue analysis, hydrophobicity studies, and the use of TLC and thin-layer radiochromatography for studies of pesticide metabolism, degradation, uptake, and related topics.

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Upton, Roy T. "Use of High-Performance Thin Layer Chromatography by the American Herbal Pharmacopoeia." Journal of AOAC INTERNATIONAL 93, no. 5 (September 1, 2010): 1349–54. http://dx.doi.org/10.1093/jaoac/93.5.1349.

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Abstract TLC characterizations are among the key identity tests in most pharmacopoeial monographs. Pharmacopoeial standards are typically used by industry as a basis for meeting QC requirements and current good manufacturing practices (cGMPs). TLC is a relatively low-cost, highly versatile tool for developing specifications for raw materials, as well as for the various preparations for which pharmacopoeial standards are created. In addition to its use in the development of identity tests, TLC is a valuable tool for screening plant samples that pharmacopoeias must review in the development of monographs and botanical reference materials (BRMs). Specifically, HPTLC is the ideal TLC technique for these purposes because of its increased accuracy, reproducibility, and ability to document the results, compared with standard TLC. Because of this, HPTLC technologies are also the most appropriate TLC technique for conformity with GMPs. This article highlights the manner in which HPTLC is used by the American Herbal Pharmacopoeia (AHP) in the development of AHP monograph identity standards, the identification of adulterating species, and the development of AHP-verified BRMs.

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Pant, Deepak. "Waste glass as absorbent for thin layer chromatography (TLC)." Waste Management 29, no. 7 (July 2009): 2040–41. http://dx.doi.org/10.1016/j.wasman.2009.03.023.

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Jaiswal, A. K. "STANDARD OPERATING PROCEDURE (SOP) FOR THIN LAYER CHROMATOGRAPHY (TLC)." International Journal of Medical Laboratory Research 06, no. 02 (2021): 69–74. http://dx.doi.org/10.35503/ijmlr.2021.6210.

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Kato, Haruyasu, Yuji Nagai, Katsuhiko Yamamoto, and Yoshio Sakabe. "Determination of Polysorbates in Foods by Colorimetry with Confirmation by Infrared Spectrophotometry, Thin-Layer Chromatography, and Gas Chromatography." Journal of AOAC INTERNATIONAL 72, no. 1 (January 1, 1989): 27–29. http://dx.doi.org/10.1093/jaoac/72.1.27.

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Abstract A method is presented for the detection of polysorbates (PSs) in 8 kinds of processed foods by colorimetric and thin-layer chromatographic (TLC) techniques. The PSs are extracted from processed foods with a mixture of methylene chloride and ethanol by using an Extrelut column. The extract is further purified by using a silica gel column. The PS extract is complexed with cobalt-thiocyanate (Cothiocyanate) reagent and is determined spectrophotometrically at 620 nm. The recoveries and coefficients of variation for 8 kinds of processed foods fortified with 0.1% PS 80 were 67.9-94.6% and 4.0- 11.3%, respectively. The detection limit of TLC corresponded to 50 mg PS 80/kg. PS identity was confirmed by infrared spectrophotometry of PS extract, and gas chromatography of fatty acids and thin layer chromatography of POE-sorbitan residues after saponification.

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Russo, Roberto, and Remo Reggiani. "Rapid separation of seed glucosinolates from Camelina sativa by thin layer chromatography." International Journal of Plant Biology 3, no. 1 (October 16, 2012): 4. http://dx.doi.org/10.4081/pb.2012.e4.

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A thin layer chromatography (TLC) method has been developed for the quantitative analysis of glucosinolates extracted from <em>Camelina sativa</em>. This procedure resolves the same long-chain glucosinolates as high-performance liquid chromatography but increases simultaneous sample size to 18. The TLC method saves time and solvent, and can be applied to screening of <em>Camelina</em>.

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Krzynowek, Judith, and Laurie J. Panunzio. "Practical Application of Thin-Layer Chromatography for Detection of Polyphosphates in Seafood." Journal of AOAC INTERNATIONAL 78, no. 5 (September 1, 1995): 1328–32. http://dx.doi.org/10.1093/jaoac/78.5.1328.

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Abstract The practical application of previously published thin-layer chromatographic (TLC) methods to polyphosphate detection in seafood was determined. Exogenous polyphosphates are distinguishable from naturally occurring phosphates by using TLC; their detection can be enhanced by sampling techniques. Polyphosphates will eventually hydrolyze to monophosphates and make detection virtually impossible. Hydrolysis and therefore, nondetection, is accelerated by certain commercial practices. Results indicate that TLC detection of added phosphates can be used as an inspection tool for fresh products and for frozen products stored about 1 year.

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Saibaba, S. V., and P. Shanmuga Pandiyan. "High Performance Thin Layer Chromatography: A Mini Review." Volume 2, Issue 4: October 2016 – December 2016 2, no. 4 (November 15, 2016): 219–26. http://dx.doi.org/10.32463/rphs.2016.v02i04.43.

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High Performance Thin layer Chromatography (HPTLC) technique is a sophisticated and automated form of the thin-layer chromatography (TLC) with better and advanced separation efficiency and detection limits, and is often an excellent alternative to GC and HPLC. Applications of HPTLC include phytochemical and biomedical analysis, herbal drug quantification, active ingredient quantification, fingerprinting of formulations, and check for adulterants in the formulations. HPTLC is useful in detecting chemicals of forensic concern. Various advance techniques in reference to HPTLC like hyphenations in HPTLC-MS, HPTLC-FTIR and HPTLC-Scanning Diode Laser have made HPTLC a power analytical tool in the field of analysis. Experts are of the opinion that HPTLC future to combinatorial approach and the utilization of instrumental HPTLC toward the analysis of drug formulations, bulk drugs, and natural products will increase in the future

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Thatipelli, Sujith, Achintya Kumar Mandal, and Shakila Ramachandran. "Chemical Standards and HPTLC Finger Print Profiles of a Siddha Polyherbal Formulation - Kadukkai Legiyam." International Journal of Ayurvedic Medicine 12, no. 4 (December 31, 2021): 922–26. http://dx.doi.org/10.47552/ijam.v12i4.2188.

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To study physico-chemical, phytochemical and high performance thin layer chromatography of a Siddha drug “Kadukkai Legiyam” (KL). The prepared Kadukkai Legiyam (KL) was prepared as per the standard operating procedures mentioned in literature. Then the drug was subjected to physicochemical parameters, phytochemical screening, thin layer chromatographic photo documentation (TLC), high performance thin layer chromatographic (HPTLC) finger print profile of hexane, chloroform, ethanol and hydro alcohol (1:1) extracts. Different extracts of the drug showed distinct TLC and HPTLC finger print patterns which will be unique to this drug. This study giving information about physiochemical and phytochemical analysis and HPTLC fingerprint profile of different extracts, the integration spectrum which will useful in standardizing the raw drugs and future comparison studies.

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Cserháti, Tibor, and Esther Forgács. "Structure-Retention Relationships and Physicochemical Characterization of Solutes in Thin-Layer Chromatography." Journal of AOAC INTERNATIONAL 81, no. 6 (November 1, 1998): 1105–8. http://dx.doi.org/10.1093/jaoac/81.6.1105.

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Abstract This review enumerates and critically evaluates experimental methods and calculation procedures used to elucidate the molecular basis of thin-layer chromatography (TLC) separations in both adsorption and reversed-phase modes. It addresses the quantitative relationship between molecular structure and retention and the determination of the solute physicochemical parameters by TLC.

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Sârbu, Costel. "Use of Fuzzy Regression for Calibration in Thin-Layer Chromatography/Densitometry." Journal of AOAC INTERNATIONAL 83, no. 6 (November 1, 2000): 1463–67. http://dx.doi.org/10.1093/jaoac/83.6.1463.

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Abstract A new fuzzy regression algorithm was successfully applied to calibration in thin-layer chromatography (TLC)/densitometry. Different regression techniques were also considered, and objective quality coefficients were used for evaluation of the results. Depending on the structure of the data, the fuzzy procedure can improve the results dramatically. From the results reported in this paper and other unpublished results, it appears clear that the calibration procedure based on fuzzy regression is the most suitable regression method in quantitative TLC.

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Oshima, Naohiro, Maho Saito, Mina Niino, Yuki Hiraishi, Kana Ueki, Kazuki Okoshi, Takashi Hakamatsuka, and Noriyasu Hada. "Elucidation of Chemical Interactions between Crude Drugs Using Quantitative Thin-Layer Chromatography Analysis." Molecules 27, no. 3 (January 18, 2022): 593. http://dx.doi.org/10.3390/molecules27030593.

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To elucidate the interactions between crude drugs in Kampo medicines (traditional Japanese medicines), it is important to determine the content of the constituents in a cost-effective and simple manner. In this study, we quantified the constituents in crude drug extracts using thin-layer chromatography (TLC), an inexpensive and simple analytical method, to elucidate the chemical interactions between crude drugs. We focused on five crude drugs, for which quantitative high-performance liquid chromatography (HPLC) methods are stipulated in the Japanese Pharmacopoeia XVIII (JP XVIII) and compared the analytical data of HPLC and TLC, confirming that the TLC results corresponded with the HPLC data and satisfied the criteria of JP XVIII. (Z)-ligustilide, a major constituent in Japanese Angelica Root, for which a method of quantification has not been stipulated in JP XVIII, was also quantitatively analyzed using HPLC and TLC. Furthermore, Japanese Angelica Root was combined with 26 crude drugs to observe the variation in the (Z)-ligustilide content from each combination by TLC. The results revealed that combinations with Phellodendron Bark, Citrus Unshiu Peel, Scutellaria Root, Coptis Rhizome, Gardenia Fruit, and Peony Root increased the (Z)-ligustilide content. Quantifying the constituents in crude drug extracts using the inexpensive and simple TLC method can contribute to elucidating interactions between crude drugs in Kampo medicines, as proposed by the herbal-pair theory.

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Ustyugova, Anna O., Elena G. Sumina, Varsenia Z. Uglanova, and Olga N. Novozhilova. "Thin-layer chromatography of L-carnitine in micellar and cyclodextrin mobile phases." Butlerov Communications 58, no. 5 (May 31, 2019): 62–69. http://dx.doi.org/10.37952/roi-jbc-01/19-58-5-62.

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L-carnitine (lat. Levocarnitinum, eng. Levocarnitine) is a natural substance akin to B vitamins. Normalizing metabolic processes in the human body and having a wide range of therapeutic actions, L-carnitine is widely used in cardiology, neurology, gastroenterology, and sports medicine. Currently, modern analytical techniques, such as mass spectrometry, high performance liquid chromatography, radiation methods, etc., are used to analyze L-carnitine. Most of them are rather expensive and time consuming. Thin-layer chromatography (TLC), which is notable for its simplicity, feasibility of analysis, separation efficiency and low cost, has received much less use. In this regard, the purpose of this work was to reveal the analytical capabilities of water-organic, micellar and cyclodextrin mobile phases for the analysis of L-carnitine by means of TLC. Initial L-carnitine solutions with a concentration of 20 mg/ml were prepared by diluting solutions for injections. Their chromatography was carried out by ascending thin-layer chromatography on plates of various polarities (Sorbfil, Plasmachrom, and RP-18) with a fixed sorbent layer. Aqueous solutions of surfactants (cetyltrimethylammonium bromide, cetylpyridinium chloride, sodium dodecyl sulfate, Triton X-100), of cyclodextrins (-cyclodextrin, 2-hydroxypropyl--cyclodextrin), hydroxypropyl--cyclodextrin) were used as mobile phases. The zone of the main substance (L-carnitine) was identified by treating the plate with a mixture of freshly prepared 0.1N solution of potassium permanganate and 2.0 N acetic acid (the zone was colored in a light yellow color). Main features of the chromatographic behavior of L-carnitine were revealed. Based on the calculation of the number of theoretical plates and the height equivalent to one theoretical plate, it was shown that aqueous micellar and cyclodextrin mobile phases allow one to improve the chromatographic process efficiency and the shape of the chromatographic zones of L-carnitine as compared to water-organic eluents; cheaper Sorbfil plates (Russia) can be used for practical purposes. Optimal chromatographic systems and conditions for their use in the thin-layer chromatography of pharmaceuticals and food products have been selected and substantiated.

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Pyka, Alina, Marika Budzisz, and Małgorzata Dołowy. "Validation Thin Layer Chromatography for the Determination of Acetaminophen in Tablets and Comparison with a Pharmacopeial Method." BioMed Research International 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/545703.

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Adsorption thin layer chromatography (NP-TLC) with densitometry has been established for the identification and the quantification of acetaminophen in three leading commercial products of pharmaceutical tablets coded as brand: P1 (Productno. 1), P2 (Productno. 2), and P3 (Productno. 3). Applied chromatographic conditions have separated acetaminophen from its related substances, namely, 4-aminophenol and and 4′-chloroacetanilide. UV densitometry was performed in absorbance mode at 248 nm. The presented method was validated by specificity, range, linearity, accuracy, precision, detection limit, quantitative limit, and robustness. The TLC-densitometric method was also compared with a pharmacopeial UV-spectrophotometric method for the assay of acetaminophen, and the results confirmed statistically that the NP-TLC-densitometric method can be used as a substitute method. It could be said that the validated NP-TLC-densitometric method is suitable for the routine analysis of acetaminophen in quantity control laboratories.

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Whitaker, T. B., J. W. Dickens, and A. B. Slate. "Computerized System to Quantify Aflatoxin Using Thin Layer Chromatography1." Peanut Science 17, no. 2 (July 1, 1990): 96–100. http://dx.doi.org/10.3146/i0095-3679-17-2-12.

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Abstract A microcomputer was interfaced to an instrument (spotmeter) previously designed to measure the fluorescent intensity of aflatoxin spots on thin layer chromatography (TLC) plates. Software was developed that uses a cubic regression equation to describe the relationships between the spotmeter readings and the known quantities of aflatoxin in standard spots on TLC plates. The regression technique also provides methods to detect spotting and/or measurement errors. Based on the regression equation and measurements of sample extract spots on the same TLC plate, the system computes and records the amount of aflatoxin in the sample extract spots and the concentration of aflatoxin that was in the extracted sample. The percent error associated with computed amounts of aflatoxin in sample extract spots is affected by the amount of aflatoxin in the sample extract spots and standard spots on the plate. The average percent error ranged from 14.9% for a 2.6 ng spot of 4.1% for a 13 ng spot.

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Upadhyay, Sushma. "Estimation of Drug Containing Tranquilizers by Thin Layer Chromatography (TLC)." Indian Journal of Forensic Medicine & Toxicology 12, no. 3 (2018): 166. http://dx.doi.org/10.5958/0973-9130.2018.00153.6.

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SUGIYAMA, TAKEYOSHI. "Rapid development methods of preparative large thin-layer chromatography (TLC)." Kagaku To Seibutsu 28, no. 1 (1990): 59–61. http://dx.doi.org/10.1271/kagakutoseibutsu1962.28.59.

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Mgbeahuruike, Eunice Ego, Heikki Vuorela, Teijo Yrjönen, and Yvonne Holm. "Optimization of Thin-layer Chromatography and High-Performance Liquid Chromatographic Method for Piper guineense Extracts." Natural Product Communications 13, no. 1 (January 2018): 1934578X1801300. http://dx.doi.org/10.1177/1934578x1801300109.

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In this study, a thin-layer chromatography (TLC) and a high performance liquid chromatographic (HPLC) methods were developed for the chemical profiling, qualitative and quantitative analysis of P. guineense extracts. To obtain a chromatogram with satisfactory resolution and favorable retention time, DryLab software was used to simulate and optimize a HPLC method for the analysis of P. guineense extracts. The aim was to achieve the best possible overall resolution while keeping the analysis time and solvent consumption to a minimum. With the optimized method, a total of 16 main components in the extract were separated with favorable resolution. Optimal TLC conditions were also developed using solvents of various solvent strength (ST) and solvent selectivity (PS) values. The mobile phase composition was systematically tested using various proportions of solvents differing in ST and PS values under the same experimental conditions. During the optimization, emphasis was set on achieving the best possible overall separation of the main components of the extracts (for example piperine). In addition, the effects of the developing chamber was tested using three types of unsaturated chamber conditions: horizontal chamber in sandwich configuration, horizontal chamber in non-sandwich configuration and twin-trough vertical chamber. During the study, a TLC method was developed, and the best mobile-phase composition giving favorable resolution of the bands was toluene: ethyl acetate (PS 6-4 corresponding to 60:40 % v/v). The developing chamber conditions did not affect the TLC separation efficacy in the analysis of P. guineense extracts. The HPLC method was applied to determine the percentage content of piperine in P. guineense. The piperine content was 0.43 % w/w, linearity (0.997), interday precision (% relative standard deviation (RSD), 1.6), intraday precision (% RSD, 2.7 – 5.9), recovery (98.4%), limit of detection (0.001 μg /mL) and limit of quantification (0.003 μg /mL).

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Liu, Xing Rong, Jian Zheng, Dao Chen Zhu, and Yuan Mei Chen. "Determination of Puerarin and Daidzin from Pueraria Root Based on Chromatography." Advanced Materials Research 524-527 (May 2012): 2273–77. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.2273.

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Combine thin layer chromatography ( TLC ) with high performance liquid chromatography ( HPLC ) detection of kudzu root isoflavones, to establish a rapid and accurate method to determine the component content of Puerarin and daidzin in Radix Puerariae.Though study on the optimization analysis of Puerarin Content in Radix Puerariae and daidzin content chromatography in a variety of conditions, including TLC developing solvent and options of coloration, and HPLC chromatographic separation conditions and detection characteristics of TLC and HPL, to get the best Chromatographic separation conditions and make a comparison with Puerarin pharmacopoeia test methods.The experimental results show that: TLC has the advantages of simple operation, rapid, reproducible, rapid identification of Puerarin and daidzin , HPLC with good stability, great accuracy and high precision that can be detected in puerarin and daidzin content. TLC and HPLC is a simple, fast, accurate method and contribute to the establishment of puerarin medicine standardized quality evaluation system and comprehensive utilization and development of Pueraria resources.

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Muhammed, Hadiza, Lare H. Abdullahi, Fatima G. Mayaki, and Usman H. Boko. "Phytochemical compositions, antimicrobial activities, and thin layer chromatography analysis of aqueous, and methanol extracts of Tectona grandis leaf." AROC in Natural Products Research 01, no. 01 (July 24, 2021): 44–51. http://dx.doi.org/10.53858/arocnpr01014451.

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Background: Teak (Tectona grandis) from the family Verbenaceae/Lamiaceae is indigenous to India, other tropical countries, and one of the naturally discovered plants to be known by scientists due to its high potential and effectiveness in disease preventive and curative action. The present study evaluated the phytochemical composition, anti-microbial activity of methanol and aqueous extract of Tectona grandis leaf, and characterized the extracts using thin-layer chromatography (TLC). Methods: The phytochemical, anti-microbial activity thin layer chromatography (TLC) analysis was conducted using established protocols. Results: The results revealed that the methanol extract of teak plant leaves contains steroids, tannins, saponin, coumarin, protein, carbohydrates, alkaloids, diterpenes, phytosterol, phlobatannin while the aqueous extract contains tannins, saponin, coumarin, protein, carbohydrate, alkaloid, diterpenes, phytosterol, and phlobatannins. The methanol extract of Tectona grandis showed the highest activity on S. epidermasis (14mm) and against S.aureus (10mm) at a concentration of 40mg/ml followed by the activities of aqueous extract of teak plant leaf against Candida Albicans (8mm) at a concentration of 40mg/ml. The extract had no inhibitory effect at all other concentrations. Conclusion: The result confirmed that Tectona grandis contain several bioactive phytochemicals that can be explored for the treatment of pathogenic microorganism.

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Everall, Neil J., John M. Chalmers, and Ian D. Newton. "In situ Identification of Thin-Layer Chromatography Fractions by FT Raman Spectroscopy." Applied Spectroscopy 46, no. 4 (April 1992): 597–601. http://dx.doi.org/10.1366/0003702924124961.

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The use of near-IR-FT Raman spectroscopy for the in situ analysis of fractions on TLC plates is described. The detection of additives in use in the plastics industry is used as an example. Reasonable-quality spectra were obtained from sample loadings equivalent to about 3 μg mm−2 in the most favorable case. Background fluorescence was not a problem, either from the adsorbent or the adsorbate, even when fluorescor was present to aid spot visualization. Similarly, staining with iodine to identify spot positions did not degrade the FT Raman spectra. When a mixture of three additives (200 μg of each) was eluted on a silica TLC plate, two of the additives gave good Raman spectra, sufficient for identification. The third component, a weaker scatterer, had spread over such a large area that the concentration was too weak to give a Raman spectrum visible above the background features from the TLC adsorbent. The concentration of the eluted spot is the limiting factor in this approach since the Raman experiment samples only about 1 mm2 of the total sample area. However, component detection is clearly feasible with the use of this technique, and advances in detector technology should substantially reduce the sample loadings required to effect identification, although it must be realized that background Raman features from the TLC adsorbent will ultimately obscure the spectrum of very dilute loadings of additives. In such cases, sample concentration on the plate will be necessary. A brief comparison with conventional Raman spectra obtained with 514-nm excitation is also made. While good spectra of one additive on silica were obtained, this approach could not be used with plates that contained added fluorescor or that had been stained with iodine for spot visualization, owing to intense background fluorescence. The approach was also prone to fluorescence form the TLC fraction itself and sample degradation.

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Pengon, Sirikarn, Chutima Limmatvapirat, and Sontaya Limmatvapirat. "Simplified Qualitative Analysis of Glycerides Derived from Coconut Oil Using Thin Layer Chromatography." Advanced Materials Research 506 (April 2012): 182–85. http://dx.doi.org/10.4028/www.scientific.net/amr.506.182.

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Coconut (Cocos nucifera L.) oil is composed predominately of medium-chain triglycerides which have been reported to be beneficial to human health. It also contains free fatty acids (FFAs) which can combine with glycerol to form monoglycerides, diglycerides, and triglycerides. The analysis of FFAs and their glycerides has been proposed to assess the quality of coconut oil used as raw materials in various industrial fields. The aim of this study was to develop the qualitative method for investigation of FFA and their glycerides in coconut oil using thin layer chromatography (TLC). Coconut oil and standards of FFA and their glycerides were chromatographed separately on Silica gel 60 F254 TLC plates using hexane: ether: acetic acid (60:40:1) and hexane: ethyl acetate: acetic acid (60:40:0.5) as solvent systems A and B, respectively. The spots on developing TLC plates were detected and compared using 254-nm UV light and iodine vapor. The results showed that the resolution of solvent system A was better than that of solvent system B. However, both solvent systems were used to confirm the results. The retention factor (Rf) values of the components were in good agreement with their polarity. This method should provide a guideline for qualitative analysis of coconut oil.

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Agatonovic-Kustrin, Snezana, and David W. Morton. "The Power of HPTLC-ATR-FTIR Hyphenation in Bioactivity Analysis of Plant Extracts." Applied Sciences 10, no. 22 (November 20, 2020): 8232. http://dx.doi.org/10.3390/app10228232.

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Given the simplicity in sample preparation and application, thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) as its most enhanced form are commonly used to separate and identify complex mixtures in solution [...]

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García-Rojas, Nancy Shyrley, Abigail Moreno-Pedraza, Ignacio Rosas-Román, Enrique Ramírez-Chávez, Jorge Molina-Torres, and Robert Winkler. "Mass spectrometry imaging of thin-layer chromatography plates using laser desorption/low-temperature plasma ionisation." Analyst 145, no. 11 (2020): 3885–91. http://dx.doi.org/10.1039/d0an00446d.

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Isnaeni, Isnaeni, Andri Astuti, and Muhammad Yuwono. "Validation of Thin-Layer Chromatography-Bioautographic Method for Determination of Streptomycin." JURNAL FARMASI DAN ILMU KEFARMASIAN INDONESIA 4, no. 1 (August 3, 2018): 34. http://dx.doi.org/10.20473/jfiki.v4i12017.34-38.

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Background: A simple bio-assay for determination of streptomycin hyphenated with planar chromatography techniques was developed. Objective: This study aims to validate the method for identification and determination of streptomycin in injection preparations with TLC-bioautography. Methods: Thin Layer Chromatography (TLC) was performed on the silica Gel GF-254 using KH2PO4 solution as mobile solvent. The visualization was performed by spraying 2% resorcinol. Direct bi autography was developed using Escherichia coli ATCC 25922 as a bacterial test, grown on the nutrient agar medium at 37oC for 24 hours. The method was validated corresponding to linearity, limit of detection (LOD), intra day precision, and accuracy parameters. The accuracy was measured using streptomycin injection as a sample. Results: The Results showed that the KH2PO4 solution at 7.5% concentration was found to be the optimized solvent with Rf value of 0.5. The linear equation was y = 10.176x + 4.046 at 150 - 350 µg/mL concentration range with the linearity coefficient, Limit of Detection, accuracy, and variation coefficient were 0.9907; 40 ppm; 96.37 + 2.22% (with an RSD value of 2.31%); and 1.63 respectively. Conclusion: The prospective TLC-bioautographic method was applied for the identification and determination of streptomycin in a preparation using a single eluent KH2PO4. The eluent system optimization remains necessary for the identification and determination of the mixture of streptomycin with other antibiotics, such as aminoglycoside groups.

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Fong, Andrew, and Gary M. Hieftje. "Near-IR Spectroscopic Examination of Thin-Layer Chromatography Plates in the Diffuse Transmittance Mode." Applied Spectroscopy 48, no. 3 (March 1994): 394–99. http://dx.doi.org/10.1366/0003702944028317.

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The nondestructive detection of analyte spots on high-performance thin-layer chromatography (HPTLC) plates is demonstrated with the use of near-IR spectrometry (NIRS). The resulting hyphenated technique is called Thin-Layer Chromatography-Near-Infrared Spectrometry (TLC-NIRS). A transmittance geometry is employed, and a set of 18 interference filters is used for wavelength selectivity. Plate-thickness nonuniformity and varying amounts of water vapor adsorption onto the silica-gel TLC plates were found to be the major complications. Variations in silica-gel thickness could be compensated for by obtaining reference spectral scans of the HPTLC plates before performing the chromatography. The effects of water-vapor adsorption were reduced through use of a partial least-squares calibration model. Detection limits near 1 μg were obtained.

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Pennington, Linda J. "Thin Layer Chromatography and Densitometric Determination of Aflatoxins in Mixed Feeds Containing Citrus Pulp." Journal of AOAC INTERNATIONAL 69, no. 4 (July 1, 1986): 690–96. http://dx.doi.org/10.1093/jaoac/69.4.690.

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Abstract A method for the accurate one-dimensional thin layer chromatographic (TLC) determination of aflatoxins B1, B2, G1, and G2 in mixed feeds is presented. The aflatoxins are extracted from the sample with chloroform and purified by solvent partitioning. Each aflatoxin is separated from pulp interference by thin layer chromatography on aluminumbacked silica plates. The separated aflatoxins are detected by fluorescence densitometry. Average recoveries for samples spiked from 10 to 100 ppb B1 and G1 and from 3 to 30 ppb B2 and G2 are 82, 84, 95, and 94% for B1, B2, G1, and G2, respectively. The above recovery data, when analyzed for overall method repeatability, produced relative standard deviations of 6.8, 4.3, 6.9, and 7.6% for B1, B2, G1, and G2, respectively. Minimum detection level is less than 1 ppb for each aflatoxin. B1 is confirmed by trifluoroacetic acid derivative formation on a silica TLC plate

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Leaver, Ian H., David M. Lewis, and David J. Westmoreland. "Analysis of Wool Lipids Using Thin-Layer Chromatography with Flame Ionization Detection." Textile Research Journal 58, no. 10 (October 1988): 593–600. http://dx.doi.org/10.1177/004051758805801006.

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This paper examines the usefulness of thin-layer chromatography (TLC), coupled with an automated quantitative detection system based on flame ionization detection (FID), for the qualitative and quantitative determination of lipids in wool. The latroscan TLC-FID system has been used to determine the composition of the solvent soluble material (internal lipids) isolated from wool after Soxhlet extraction with a chloroform/methanol azeotrope, and to investigate whether scouring treatments affect the composition of the internal lipids. Changes in the composition of wool grease that occur as a result of exposure to sunlight (behind glass) and during weathering in the fleece are also examined.

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Livaja-Popovic, Dragana, Eva Loncar, Lidija Jevric, and Radomir Malbasa. "Reversed-phase thin-layer chromatography behavior of aldopentose derivatives." Chemical Industry 66, no. 3 (2012): 365–72. http://dx.doi.org/10.2298/hemind111012099l.

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Quantitative structure-retention relationships (QSRR) have been used to study the chromatographic behavior of some aldopentose. The behavior of aldopentose derivatives was investigated by means of the reversed-phase thin-layer chromatography (RP TLC) on the silica gel impregnated with paraffin oil stationary phases. Binary mixtures of methanol-water, acetone-water and dioxane-water were used as mobile phases. Retention factors, RM0, corresponding to zero percent organic modifier in the aqueous mobile phase was determined. Lipophilicity C0 was calculated as the ratio of the intercept and slope values. There was satisfactory correlation between them and log P values calculated using different theoretical procedures. Some of these correlations offer very good predicting models, which are important for a better understanding of the relationships between chemical structure and retention. The study showed that the hydrophobic parameters RM0 and C0 can be used as a measures of lipophilicity of investigated compounds.

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Petz, Michael, Roy Solly, Moira Lymburn, and Mike H. Clear. "Thin-Layer Chromatographic Determination of Erythromycin and Other Macrolide Antibiotics in Livestock Products." Journal of AOAC INTERNATIONAL 70, no. 4 (July 1, 1987): 691–97. http://dx.doi.org/10.1093/jaoac/70.4.691.

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Abstract A method is described for determination of 4 macrolide antibiotics in livestock products. Erythromycin, tylosin, oleandomycin, and spiramycin were extracted from animal tissues, milk, and egg with acetonirrile at pH 8.5. Cleanup was done by adding sodium chloride and dichloromethane, evaporating the organic layer, and subsequent acid/ base partitioning. After the antibiotics were separated by thin-layer chromatography (TLC), they were reacted with xanthydrol and could be detected as purple spots down to 0.02 mg/kg without interference by other commonly used therapeutic drugs (23 were tested). Anisaldehyde- sulfuric acid, cerium sulfate-molybdic acid, phosphomolybdic acid, and Dragendorff s reagent proved to be less sensitive as visualizing agents. For quantitation, TLC plates were scanned at 525 nm. Recoveries were between 71 and 96% for erythromycin and tylosin in liver, muscle, and egg at the 0.1-0.5 mg/kg level and 51% for erythromycin in milk at the 0.02 mg/kg level (coefficient of variation = 10-18%). Bioautography with Bacillus subtilis was used to confirm results, in addition to TLC analysis of derivatized antibiotics and liquid chromatography with electrochemical detection. Various derivatization procedures for erythromycin were investigated for improved ultra-violet or fluorescence detection in liquid chromatography.

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Wang, Meng, Yirong Zhang, Ruijie Wang, Zhibin Wang, Bingyou Yang, and Haixue Kuang. "An Evolving Technology That Integrates Classical Methods with Continuous Technological Developments: Thin-Layer Chromatography Bioautography." Molecules 26, no. 15 (July 31, 2021): 4647. http://dx.doi.org/10.3390/molecules26154647.

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Thin-layer chromatography (TLC) bioautography is an evolving technology that integrates the separation and analysis technology of TLC with biological activity detection technology, which has shown a steep rise in popularity over the past few decades. It connects TLC with convenient, economic and intuitive features and bioautography with high levels of sensitivity and specificity. In this study, we discuss the research progress of TLC bioautography and then establish a definite timeline to introduce it. This review summarizes known TLC bioautography types and practical applications for determining antibacterial, antifungal, antitumor and antioxidant compounds and for inhibiting glucosidase, pancreatic lipase, tyrosinase and cholinesterase activity constitutes. Nowadays, especially during the COVID-19 pandemic, it is important to identify original, natural products with anti-COVID potential compounds from Chinese traditional medicine and natural medicinal plants. We also give an account of detection techniques, including in situ and ex situ techniques; even in situ ion sources represent a major reform. Considering the current technical innovations, we propose that the technology will make more progress in TLC plates with higher separation and detection technology with a more portable and extensive scope of application. We believe this technology will be diffusely applied in medicine, biology, agriculture, animal husbandry, garden forestry, environmental management and other fields in the future.

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Novak, Frank P., and David M. Hercules. "Thin Layer Chromatography-Laser Mass Spectrometry (TLC-LMS) of Triphenylmethane Dyes: Initial Results." Analytical Letters 18, no. 4 (January 1985): 503–18. http://dx.doi.org/10.1080/00032718508066150.

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Rossini, Carmen, Enrique Pandolfi, Eduardo Dellacassa, and Patrick Moyna. "Determination of 1,8-Cineole in Eucalyptus Essential Oils by Thin-Layer Chromatography and Densitometry." Journal of AOAC INTERNATIONAL 78, no. 1 (January 1, 1995): 115–17. http://dx.doi.org/10.1093/jaoac/78.1.115.

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Abstract A thin-layer chromatography (TLC) method with scanning is described for evaluation of the 1,8-cineole content of Eucalyptus essential oils. Samples were developed on silica gel G 60 with light petroleum–chloroform (70 + 30) as mobile phase. Color was developed with 4-dimethylaminobenzal-dehyde–sulfuric acid reagent. The absorbance of colored spots was measured at 460 nm. The response was linear between 15 to 75 μg of 1,8-cineole, with a correlation coefficient of 0.9997. The results of each assay were compared with those from gas–liquid chromatography (GLC). The TLC to GLC ratio was constant (0.92).

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Lu, Jing, Hong-yan Ma, Wei Zhang, Zhi-guo Ma, and Shun Yao. "Separation of Berberine Hydrochloride and Tetrahydropalmatine and Their Quantitative Analysis with Thin Layer Chromatography Involved with Ionic Liquids." Journal of Analytical Methods in Chemistry 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/642401.

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[BMIM]OH was used in mobile and stationary phase of thin layer chromatography (TLC) to analyze berberine hydrochloride and tetrahydropalmatine for the first time. Supported imidazole ionic liquid with hydroxide ion on silica gel (SiO2·Im+·OH−) was synthesized through simple procedure and characterized by Fourier transform infrared spectroscopy (FT-IR), elemental analysis, and scanning electron microscope (SEM). Moreover, on the plates prepared by SiO2·Im+·OH−, the contents of the above alkaloids in the Chinese patent medicine (CPM) of “Stomacheasy” capsule were successfully determined by TLC scanner. The key conditions and chromatographic behaviors were also investigated in detail. According to similar ways, ionic liquids (ILs) also can be used in other planar chromatographies in two modes. This study is expected to be helpful in expanding the application of IL and its bonded silica gel in TLC separation field.

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Journal articles on the topic 'Thin layer chromatography (TLC)'

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