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1
Idinyang, Solomon. "Automated liquid handling systems for microfluidic applications." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/44681/.
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Advances in microfluidic research have improved the quality of assays performed in micro-scale environments. Improvement of liquid handling techniques has enabled efficient reagent and drug use while minimising waste. The requirements for the applied techniques vary with applications and a custom integrated liquid handling solution was developed to accomplish some of these applications with minimal changes to the system. It is desirable to employ this technology to neuroscience research that requires a fluidic system that can test theories of reinforcement learning in neuronal cultures. An integrated system is therefore required to implement transport and manipulation of media and drugs loaded in a microfluidic device. One requirement for such an integrated system for liquid handling is a transport mechanism to deliver reagents and nutrients to cultures. A liquid flow control system is required to allow precise and timely control of flow rates through a microfluidic device. This can be extended to enable more sophisticated drug delivery approaches like gradient generation, spatial drug distribution and high temporal resolution of the drugs delivered. Another requirement for an integrated system is a liquid loading system that is capable of inserting specified drugs into the flow line. Such a loading system would allow any number of drugs to be loaded during an experimental process to the microfluidic device containing cells as part of an assay. The integration of these systems will allow researchers take advantage of the combined systems. Software development process should also be undertaken to improve the modularity of the integrated system so that hardware changes have marginal effects on the system operation. The project scope was the development of these liquid handling systems as well as their integration in hardware and software to enable their spatio-temporal drug delivery to neuronal cultures in microfluidic devices. The approach was to optimise performance of custom liquid handling system which was developed to realise fast flow rate changes within 1 second interval. Macro- and micro-scale solutions have been investigated in order to realise effective off-chip liquid loading capabilities. Emphasis has been placed on ease of use, modularity, rapid prototyping and precision. A commercial autoloader was identified as a starting point for sequential drug delivery. This was characterised for suitability and the constraints with this setup was used to identify additional requirements for the development of a novel sequential liquid injection system. The design process of the novel liquid injection system was unable to realise a working system due to mechanical and operational challenges encountered. A modular on-chip liquid manipulation system has been investigated and proposed to realise the sequential injection requirements. Rapid prototyping techniques that can promote ubiquitous microfluidic applications have been identified and verified. An integrated liquid manipulation system has been developed using the commercial autosampler that enables sequential loading of agonists into the microfluidic device as well as reliable chemical signalling of the loaded drugs by switching flow rates of the inputs to the device. This system will be beneficial towards research of other cell types within other research fields requiring similar functionality.
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Liu, Guangbo, Clayton Lanham, J. Ross Buchan, and Matthew E. Kaplan. "High-throughput transformation of Saccharomyces cerevisiae using liquid handling robots." PUBLIC LIBRARY SCIENCE, 2017. http://hdl.handle.net/10150/623861.
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Saccharomyces cerevisiae (budding yeast) is a powerful eukaryotic model organism ideally suited to high-throughput genetic analyses, which time and again has yielded insights that further our understanding of cell biology processes conserved in humans. Lithium Acetate (LiAc) transformation of yeast with DNA for the purposes of exogenous protein expression (e.g., plasmids) or genome mutation (e.g., gene mutation, deletion, epitope tagging) is a useful and long established method. However, a reliable and optimized high throughput transformation protocol that runs almost no risk of human error has not been described in the literature. Here, we describe such a method that is broadly transferable to most liquid handling high-throughput robotic platforms, which are now commonplace in academic and industry settings. Using our optimized method, we are able to comfortably transform approximately 1200 individual strains per day, allowing complete transformation of typical genomic yeast libraries within 6 days. In addition, use of our protocol for gene knockout purposes also provides a potentially quicker, easier and more cost-effective approach to generating collections of double mutants than the popular and elegant synthetic genetic array methodology. In summary, our methodology will be of significant use to anyone interested in high throughput molecular and/or genetic analysis of yeast.
3
Stoskopf, Jeffrey Alan. "The assessments of the flammable liquid storage/dispensing/handling rooms at XYZ Corporation." Online version, 2001. http://www.uwstout.edu/lib/thesis/2002/2002stoskopfj.pdf.
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Akochi-Koblé, Emmanuel. "Evaluation of sphagnum moss and chemical compounds for management of odor and use of liquid hog manure." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59944.
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Liquid hog manure (LHM) obtained from the Macdonald College farm was used in experiments aimed at (a) reducing the odor associated with LHM during handling and (b) conserving the fertilizer capacity of LHM. Various chemical treatments and sphagnum moss (SM) were evaluated to achieve the above objectives. Direct acidification to $<$ pH 5.0, sphagnum moss (SM) and its combination with aluminum sulfate (AS) resulted in significant (p $<$ 0.05) reduction in ammonia losses during storage of LHM. The SM and SM/AS combination also significantly (p $<$ 0.05) reduced both odor presence and offensiveness. Gas chromatographic (GC) and GC/mass spectrometry (GC/MS) analysis indicated the absence of certain malodor compounds and lower peak areas of certain compounds in the SM and SM/AS treatments when compared to the controls. Investigations with barley seeding revealed that treatments which reduced the malodor of the LHM did not significantly (p $<$ 0.05) affect the nitrogen fertilization capacity of the LHM, as indicated by plant dry matter yield.
5
Bettelli, Marco. "Sviluppo di un sistema innovativo di liquid handling automatizzato per un dispositivo lab-on-a-chip." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
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Cellply è un'azienda del settore biomedicale che sta sviluppando una piattaforma IVD (In-Vitro Diagnostic) in grado di fornire un'analisi personalizzata testando la risposta di farmaci antitumorali su campioni biologici prelevati da pazienti. Il cuore del sistema è un Lab-on-a-chip che si basa su una tecnologia microfluidica brevettata, denominata Open Microwell, che permette di gestire e analizzare i campioni di cellule tramite elaborazione di immagini in modo standardizzato e automatizzato[1].
Per lo sviluppo della piattaforma di Cellply si è reso necessario sviluppare un sistema di liquid handling, in modo da automatizzare e rendere più precisa e ripetibile la gestione dei campioni biologici. La parte fondamentale del sistema di liquid handling è un pipettatore automatico, cioè un componente in grado di automatizzare tutti quei procedimenti che, in un laboratorio biologico, vengono tipicamente realizzati tramite pipette manuali.
Il pipettatore viene montato su un sistema meccanico multiassiale (XY Portal) in grado di posizionarlo con precisione in un'area di lavoro (working area) ben definita, all'interno della quale avviene il trasferimento dei liquidi.
Il lavoro di tesi ha riguardato lo sviluppo e l'implementazione del software di controllo dell'XY Portal. La progettazione è stata realizzata sfruttando l'ambiente di sviluppo LabVIEW per il linguaggio di programmazione grafico di National Instruments.
Dopo una prima fase in cui sono stati definiti i requisiti e analizzati i relativi rischi, si è passati allo sviluppo vero e proprio della libreria software per poi terminare con l'esecuzione dei test necessari alla verifica della corretta implementazione dei suddetti requisiti. La libreria software è stata progettata seguendo le specifiche di progetto necessarie all'integrazione della stessa all'interno del software principale di Cellply che gestisce le varie risorse hardware che compongono il dispositivo diagnostico in fase di sviluppo.
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Fetzer, Molly M. "Comparative risk assessment of a cylinder handling system and a bulk liquid distribution system for Trichlorosilane." Online version, 1998. http://www.uwstout.edu/lib/thesis/1998/1998fetzerm.pdf.
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Campbell, Allan J. "Design and evaluation of liquid swine manure injectors for potato nutrient placement." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0025/NQ50124.pdf.
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Räbiger, Klaus Edmund. "Fluid dynamic and thermodynamic behaviour of multiphase screw pumps handling gas-liquid mixtures with very high gas volume fractions." Thesis, University of South Wales, 2009. http://hdl.handle.net/10265/561.
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Barkenäs, Emelie. "Automation of a solid-phase proximity ligation assay for biodefense applications." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-215448.
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The extent of devastation caused by a biological warfare attack is highly correlated to the time from release to detection. As a step towards lowering the detection time the international project TWOBIAS was launched. Here, the main goal is to develop an automated, specific and sensitive combined detection and identification instrument capable of identifying a biological threat within an hour. The identification unit is comprised of a sample preparation module, an amplification module and a detection module and utilizes a proximity ligation assay in combination with circle-to-circle amplification in order to detect a biological threat. This thesis describes the automation of the sample preparation steps of the assay and the integration with the downstream units. The functionality of the sample preparation module was verified by subjecting it to biological samples in a laboratory and at a real-life location. The results showed that the sample preparation module was capable of preparing a sample collected in a complex environment with the same results as a sample prepared in a laboratory.
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Tillich, Ulrich Martin. "Adaptive Evolution und Screening bei Cyanobakterien." Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2015. http://dx.doi.org/10.18452/17184.
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Ziel dieser Arbeit war die Erhöhung der Temperaturtoleranz des Cyanobakteriums Synechocystis sp. PCC 6803 mittels ungerichteter Mutagenese und adaptiver Evolution. Trotz des erneuten Interesses an Cyanobakterien und Mikroalgen in den letzten Jahren, gibt es nur relativ wenige aktuelle Studien zum Einsatz dieser Methoden an Cyanobakterien. Zur Analyse eines mittels Mutagenese erzeugten Gemischs an Stämmen, ist es von großem Vorteil Hochdurchsatz-Methoden zur Kultivierung und zum Screening einsetzen zu können. Auf Basis eines Pipettierroboters wurde solch eine Plattform für phototrophe Mikroorganismen neu entwickelt und folgend stetig verbessert. Die Kultivierung erfolgt in 2,2ml Deepwell-Mikrotiterplatten innerhalb einer speziell angefertigten Kultivierungskammer. Schüttelbedingungen, Beleuchtung, Temperatur und CO2-Atmosphäre sind hierbei vollständig einstellbar.Die Plattform erlaubt semi-kontinuierliche Kultivierungen mit automatisierten Verdünnungen von hunderten Kulturen gleichzeitig. Automatisierte Messungen des Wachstums, des Absorptionsspektrums, der Chlorophyllkonzentration, MALDI-TOF-MS sowie eines neu entwickelten Vitalitätsassays wurden etabliert. Für die Mutagenese wurden die Letalität- und die nicht-letale Punktmutationsrate von ultravioletter Strahlung und Methylmethansulfonat für Synechocystis charakterisiert. Synechocystis wurde mit den so ermittelten optimalen Dosen mehrfach behandelt und anschließend einer in vivo Selektion unterzogen. Somit wurde dessen Temperaturtoleranz um bis zu 3°C erhöht. Über die Screeningplattform wurden die thermotolerantesten monoklonalen Stämme identifiziert. Nach einer Validierung wurde das vollständige Genom der Stämme sequenziert. Hierdurch wurden erstmals Mutationen in verschiedenen Genen mit der Langzeittemperaturtoleranz von Synechocystis in Verbindung gebracht. Bei einigen dieser Gene ist es sehr unwahrscheinlich, dass sie mittels anderer Verfahren hätten identifiziert werden können.The goal of this work was the increase of the thermal tolerance of the cyanobacteria Synechocystis sp. PCC 6803 via random mutagenesis and adaptive evolution. Even with the renewed interest in cyanobacteria in the recent years, there is relatively limited current research available on the application of these methods on cyanobacteria. To analyse a mixture of various strains typically obtained through random mutagenesis, a method allowing high-throughput miniaturized cultivation and screening is of great advantage. Based on a pipetting robot a novel high-throughput screening system suitable for phototrophic microorganisms was developed and then constantly improved. The cultivation was performed in 2,2 ml deepwell microtiter plates within a cultivation chamber outfitted with programmable shaking conditions, variable illumination, variable temperature, and an adjustable CO2 atmosphere. The platform allows semi-continuous cultivation of hundreds of cultures in parallel. Automated measurements of growth, full absorption spectrum, chlorophyll concentration, MALDI-TOF-MS, as well as a novel vitality measurement protocol, have been established. Prior to the mutagenesis, the lethality and rate of non-lethal point mutations of ultraviolet radiation and methyl-methanesulphonate were characterized for Synechocystis. The thus determined optimal dosages were applied to Synechocystis followed by in vivo selection in four rounds of mutagenesis, thereby raising its temperature tolerance by 3°C. The screening platform was used to identify the most thermotolerant monoclonal strains. After validation, their whole genomes were sequenced. Thus mutations in various genes were identified which promote the strains'' thermal tolerance. For some of the genes it is very unlikely that their link to high thermal tolerance could have been identified by other approaches.
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Pfahler, Patrick [Verfasser], Lothar [Akademischer Betreuer] Oberauer, and Andreas [Akademischer Betreuer] Ulrich. "Realization of the low background neutrino detector Double Chooz: From the development of a high-purity liquid & gas handling concept to first neutrino data / Patrick Pfahler. Gutachter: Andreas Ulrich ; Lothar Oberauer. Betreuer: Lothar Oberauer." München : Universitätsbibliothek der TU München, 2012. http://d-nb.info/1031511504/34.
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Holmgren, Per. "Postmortem toxicology : aspects on interpretation /." Linköping : Univ, 2004. http://www.bibl.liu.se/liupubl/disp/disp2004/med862s.pdf.
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Patel, Hitendra Gandabhai. "An intelligent transfer-wheel system for container handling." Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284255.
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Schaufelbuhl, M. R. "Liquid bulk wax handling and storage : a systems approach to resolve a material handling problem." Thesis, 2014. http://hdl.handle.net/10210/11530.
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M.Tech. (Industrial Engineering)Material handling is never value-adding, but always increases the production costs. The objective of any new handling system should therefore be to reduce handling and then to find cost-effective solutions for those operations that cannot be eliminated. The systems approach can be used to analyse and solve material handling problems, ensuring that all alternatives are considered. This increases the likelihood of a successful project. The feasibility study should be used at the outset of a project to ensure that a shortlist of the best solutions can be made. This is done before major capital expense is incurred. Thereafter, a systematic procedure guides the project from a concept design, to a few selected option, then to the simulation of the proposed system and finally to the installation plan and construction. The systems approach is often preferred by management, because the financial and technical issues are quantified and therefore reduce the risk of a bad investment. Ultimately, a new material handling system, if required at all, should minimise production costs and therefore be an asset instead of a liability to the company.
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Jones, Benjamin Marcus. "Field Evaluation and Anaysis of a Liquid Desiccant Air Handling System." Thesis, 2008. http://hdl.handle.net/1974/1532.
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A thermal liquid desiccant air handling machine was procured, installed, and field
tested. The goal of the present investigation is to evaluate the field performance of the
machine and characterize its operation for the temperature range of a solar thermal
array. The system studied includes a natural gas boiler supplying the heat, and a
cooling tower for heat rejection. System performance was evaluated for the 50 to 90 C
temperature range, the operating range of solar thermal collectors. Cooling power
varied between 4.3 kW and 22.8 kW for this range of temperature, with a latent heat
ratio between 1.1 and 1.9, confirming that the unit is significantly dehumidifying the
process air stream. Electrical COP varied between 0.58 and 4.48. Performance data
indicates higher temperature solar collectors such as evacuated tube or double glazed
flat plat collectors would be optimum in a solar cooling application with this system.
Empirical correlations for the regenerator and conditioner components were obtained
using a multivariate linear regression model. 5 empirical relations were derived and
can be used to characterize the thermal dehumidification concept. These relations
and methods will be used in future work to simulate and optimize a solar thermal
driven dehumidification system for dedicated outdoor air systems.Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2008-09-28 04:36:36.26
16
Cheng, Chih-Ming, and 鄭志銘. "Bubble-Actuated Micro Fluidic Switches and Micropumps in Microfluidic Chips for Continuous Liquid Handling." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/33815082359238211946.
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博士國立清華大學
動力機械工程學系
95
A microfluidic system, which integrates sample pretreatment, transportation, reaction, separation and detection on a small chip, can be realized by combining several microfluidic subsystems with specific functions. For the microfluidic systems, the precise handling of small volumes of test reagents is essential. Practical microfluidic applications require an efficient way for both microscale pumping and flow control. Thus, continuous liquid handling is critical to the microfluidic system. For the handling of continuous liquid, this research focuses on the development of microfluidic system chip which is capable of pumping and guiding continuous liquid inside multi-ported microchannels. This thesis is therefore aimed at investigating two microfluidic subsystems — the 1*N micro fluidic switch and the low-power consumption micropump. In the micro fluidic switch design, we introduce a robust approach by utilizing the hydrophobic/hydrophilic properties that generate the capillary force and the barrier pressure to achieve the switching function. The distributed hydrophobic-patch design and the programmable time-sequence bubble actuation are taken advantage for the function of microfluidic switch. The design and implementation of a novel thermal-bubble-actuated 1×N micro flow switch without the need of external macro pumps is presented. The switch mechanism among different microchannels is dominated by controlling the format and the timing of power input that generates the actuation thermal-bubbles. The experimental results successfully demonstrate the switch function in a chip to guide the sample liquid into desired outlet ports via programmable time-sequence control pulses. In the micropump design, a novel actuation mechanism utilizing the roughness gradient surface to achieve the net pumping flow is investigated. This micropump is implemented by taking advantage of the electrolysis actuation, the surface tension effect and the periodic generation of electrolysis-bubble. This proposed micropump design not only achieves a net pumping flow but also resolves the main problem that exists in most electrolytic bubble actuators on the issue of degassing the insoluble gases out of microchannels. This micropump driven by a simple circuit control without mechanical moving parts is suitable for the development of low power-consumption and compact micropumps. Experimental results demonstrate the pumping function of our micropump to continuously push liquid forward based on our roughness gradient design and the periodic electrolytic-bubble generation in the microchannel. Furthermore, experimental results also show that the liquid displacement and the pumping rate could be easily and accurately controlled by adjusting the amplitude and the frequency of the applied voltage. In this study, our 1*N micro fluidic switches and the low-power consumption micropumps have been successfully demonstrated. The theoretical analysis, design, micromachining process, operating principles, and characterization are all described in this thesis. The long-term goal of this work is to integrate the micro fluidic switches and the micropumps into a closed-loop microfluidic system for specific flow guiding, specific flow injection, and precise liquid volume control.
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Gölden, Felix. "Liquid Crystal Based Microwave Components with Fast Response Times: Material, Technology, Power Handling Capability." Phd thesis, 2010. https://tuprints.ulb.tu-darmstadt.de/2203/1/GoeldenFinalNeu.pdf.
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The present thesis is concerned with tunable microwave components based on Liquid Crystals (LC). Here, the fact is utilised that LC feature at GHz frequencies as well as at optical frequencies a dielectric anisotropy along a preferential direction. By means of an electric or magnetic control field, which superimposes the RF field, this preferential direction can be reoriented and thus the permittivity effective for the RF field can be controlled. After in a preceding doctoral work the applicability of LC was demonstrated in principle, the motivation of the present work is to advance the usage of LC for microwave applications, particularly for tunable phase shifters for reconfigurable phased arrays, further toward commercial applicability. To this end, both material aspects as well as component and fabrication aspects are considered. In order to improve the dielectric properties, i.e. loss and anisotropy and hence the tunability, numerous nematic mixtures were investigated with respect to their microwave performance. Certain components could be identified which feature both high tunability and low loss. Particularly these compounds based on Diphenylacetylene or on Quarterphenyles. By employing high precision measurements it is shown that the dielectric loss strongly depends on molecular relaxations. If these relaxations are reduced, materials with loss tangents down to 0.006 and relative tunabilities of up to 25 % at 30 GHz can be synthesised. For passively tunable materials, these are exceptional values. Two different approaches were pursued in order to reduce the so far for LC-based microwave devices with layer thicknesses of several 100 µm usual response times of several seconds. On the one hand, this is the stabilisation of the LC by means of a PTFE matrix which reduced the response times considerably down to 90 ms. On the other hand, a method resembling LC display assembly technology has been developed which allows realising thin LC layers also for microwave devices. Using the fabricated tunable capacitors it could be demonstrated that with a LC layer thickness of approx. 5 µm response times faster than 100 ms and with a layer thickness of approx. 1 µm response times faster than 5 ms can be achieved. Based on these tunable capacitors a tunable phase shifter is developed which features a phase shifter performance of up to 60 degrees per dB insertion loss at 20 GHz and a response time of faster than 340 ms. Additionally, for these devices resistive bias electrodes made of Indium-Tin-Oxide were employed. The power handling capability of such devices was investigated by means of single and two tone measurements. With the single tone measurements it could be shown that the device characteristic is influenced at high power levels by self-actuation effects, however only above a certain threshold power. With the two tone measurements it could be shown that these self-actuation effects cause increased intermodulation at small tone distances (<1 kHz). However, for tone distances larger than 100 kHz IP3 values of about 60 dBm can be achieved.
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Wilkens, Marcus. "Modelling, Simulation and control of a Shortest Path Enthalpy Change Air Handling Unit with Liquid Desiccant." Thesis, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-447433.
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In an abundance of industries, production lines and facilities, a correct indoor climate is an integral part to ensure the quality of the products and also very important for its occupants. To ensure a high quality air climate it is not enough to control the air temperature, air humidity is of at least equal importance. Most heating, ventilation and air conditioning systems (HVAC), are based on multiple treatment steps that each change both temperature and humidity. Due to the correlation between the temperature and relative humidity this results in system control difficulties, and unnecessary realignments to achieve the desired outputs. The novel Shortest path enthalpy change system (SPEC), developed by AirWaterGreen (AWG) with Controlled vapor pressure technology (CVP), aims to eliminate these problems. This is done by utilizing a method that may achieve the desired air quality with only one conditioning step, transferring heat and humidity simultaneously to or from the air. To validate this technology the work of this thesis is focused on producing a viable simulator model with verification, performed by comparing to a prototype system with the same technology. By verifying the simulator, it is also possible to continue development of the system by implementing system controllers within the Simulink environment. This provides the opportunity to ultimately obtain a highly efficient HVAC system with accurate setpoint control. In addition, the possibility of optimizing system dimensions is also investigated to allow for specific case configurations. The results show that high simulator accuracy is achievable, leading to a high confidence in the results, and showing that a PID or even proportional feedback controller is able to realize satisfactory system control. The optimization of dimensions shows that parallel computing is a fast way to reduce the amount of possible configurations that satisfy specific criteria. To support further development of the control and optimization of the system and ultimately hardware implementation, this thesis suggests points of interest for future work. These points include the improvement of ancillary simulator systems and further development of the pads physical equations, to increase the accuracy of process simulations, and the continued development of more complex controllers as well as their hardware implementation. Lastly, while focus of this thesis has been on the development of a functioning and controllable system, an important addition would be a study on the energy usage of the system and identifying points of interest for decreasing the total energy used from the system.
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Chen, Yu-cheng, and 陳玉承. "Comparing the relative oxidative damage biomarkers caused by different workers handling engineered nanomaterials using online-column switching liquid chromatography tandem mass spectrometry." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/77546513761261308498.
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碩士輔仁大學
化學系
101
Nanotechnology is an emerging technology that involves manipulating substances at the nanoscale to create new classes of materials with novel and unique properties. These unique materials are commercially very useful and are being applied in many diverse sectors such as medicine, consumer products, food, agriculture, environment, energy, electronics and building materials. However, the increasing use of engineered nanomaterials also raises concerns about inadvertent exposure to these materials and the potential for adverse effects on human health and the environment. Although the mechanism underlying the correlation between engineered nanomaterials exposure and adverse effects has not fully elucidated, engineered nanomaterials-induced oxidative stress has been considered as an important molecular mechanism of engineered nanomaterials -mediated toxicity. A few epidemiological studies have reported adverse health effects associated with exposure to engineered nanomaterials (TiO2, SiO2, ITO) and DNA damage, oxidative stress and global methylation biomarkers. The aim of this study was to evaluate the relation between oxidative DNA damage (8-hydroxy-2’deoxyguanosine, 8-OHdG), oxidative stress biomarkers (8-isoprostaglandin, 8-isoPGF2α) and global methylation in workers handling engineered nanomaterials using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) Our results has shown that the univariate and multiple linear regression analysis of the different biomarkers from workers handling engineered nanomaterials, compare the levels of biomarkers 8-OHdG and v 8-isoPGF2α in different bio-fluids whether workers handling engineered nanomaterials or not, and the results shown it had significant in this models. Then, the relationship between global DNA methylation and oxidative damage biomarker 8-OHdG had statistically significant negative correlation in normal. However, the correlation would change when people expose in environment of nanomaterials. Otherwise, many studies have demonstrated that smoking would cause oxidative damage, but the factor of smoke didn’t increase oxidative damage in our study. Finally, we discussed effects of human health after long-term exposure. According to our result, the oxidative damage biomarker didn’t increased levels after exposure due to people being well-protected in working environment. The applicability of this developed method was demonstrated by analyzing human EBC, WBC, plasma and urine samples. Exposure to nanomaterials indeed caused increasing the levels of oxidative damage biomarkers and decreasing the levels of global DNA methylation, it can be said environment has great effect to human health, so we should make our effort to protect our body for cancer and chronic disease prevention.