Tesis: "Skin absorption"

1

Baker, E. J. "Absorption of drugs across the skin". Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378940.

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2

Watkinson, Adam C. "Skin absorption of prostaglandins and related compounds". Thesis, Cardiff University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407992.

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3

Wakefield, James Christopher. "Influence of skin irritation on dermal absorption". Thesis, University of Newcastle upon Tyne, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435596.

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4

Engblom, Johan. "On the phase behaviour of lipids with respect to skin barrier function". Lund, Sweden : Dept. of Food Technology, Lund University, 1996. http://books.google.com/books?id=TdFqAAAAMAAJ.

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5

Ridout, G. "Percutaneous absorption of drugs". Thesis, University of Nottingham, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373320.

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6

Neupane, Rabin. "Percutaneous absorption and Skin accumulation of ABH Carbopol gel in Porcine Ear Skin". University of Toledo Health Science Campus / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=mco1556641636092785.

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7

Al-Otaibi, Faisal Obaid. "Pharmacokinetic studies of drug absorption into human skin". Thesis, Queen Mary, University of London, 2010. http://qmro.qmul.ac.uk/xmlui/handle/123456789/361.

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Optimum therapeutic outcomes require not only proper drug selection but also effective drug delivery and monitoring. The aim of this thesis was to A) study drug delivery through the skin with a liquid formulated to promote absorption, B) develop and validate methods to analyze the drug in the samples obtained, C) assess appropriate methods to measure the transdermal delivery of drug, and D) apply to pharmacodynamics. The stability of a rectal formulation of diazepam, Diastat®, and a quality control of a topical form, TDS® diazepam, were studied using high performance liquid chromatography (HPLC) with ultraviolet absorption detection (UV). It was found that diazepam at 10 mg/mL was stable in solution at various temperatures for at least 4 weeks. A pharmacokinetic study of diazepam delivery from the TDS® delivery system was compared with delivery of the drug following rectal administration of Diastat® in 12 healthy volunteers. The TDS® diazepam was evaluated for safety and no adverse effects or events were observed. The preparation was found to be able to deliver diazepam systemically in humans, the confidence interval (CI) of the ratios for Cmax and AUC of diazepam from the two formulations A (TDS®): B (rectal) were not contained within the bioequivalence limit 80–125%, Cmax (0–72h): 7.3–14% and AUC0-72h: 20–38%. In addition, the 90% CI of desmethyldiazepam (A:B) ratio were not contained within the bioequivalence limit, Cmax (0–72h): 38–54% and AUC0-72h: 33–58%. Although not bioequivalent to Diastat® these finding suggest that skin may be an alternative method of diazepam delivery but further developments and studies would be required. The development and validation of fast, high throughput methods to evaluate tetracaine from skin tape samples was another challenge. Sensitive and reliable capillary electrophoresis with UV and HPLC-UV methods were developed and validated to measure tetracaine in skin using tape samples from volunteers given 1 mL Ametop gel (4% w/w of tetracaine) to support a pharmacokinetic drug delivery study of Ametop. The results from these validation studies demonstrated an equal ability of the two methods to measure tetracaine concentrations reproducibly and accurately. The Bland Altman test was in a range of ± 1.96 SD from the mean (SD = ± 8.02, Mean = 2.23), and percentage error (± 20%.), which show an acceptable difference. The assays were found to possess both the sensitivity and specificity necessary to measure the analyte in the skin tape stripping at the concentrations range in these tapes. Finally, observation of appropriate methods to measure the transdermal drug in vivo techniques, such as microdialysis (MD) and tape stripping (TS) have been employed by plotting a concentration time profile to investigate the capability of measuring tetracaine (pharmacokinetics) in local tissue, instead of measuring tetracaine by conventional systemic measurements. The results showed that the tetracaine Cmax concentration was higher in the stratum corneum compared with the major metabolites of tetracaine, 4- butylaminobenzoic acid (BABA) by 3 and 10 times in MD and plasma, respectively. TS samples reached the maximum concentration quicker than BABA in dialysate and plasma samples (p = 0.002). The median tmax was higher in plasma (IQR -53minutes, 95% CI: - 30– -105) compared with tape samples. The AUC and Cmax for tetracaine were higher in TS compared with BABA in MD and plasma (Mean AUC0-4h: 88582, 55594 and 13208 nM.min: Mean Cmax (0–4h), 850, 459, 110 nM, respectively). In addition, the AUC and Cmax values demonstrated that data from the TS study showed less variability compared with the data from plasma. The most variable data were for MD (CV%; AUC0-4h, 24, 63, and 85%: Cmax (0–4h), 42, 60, 80%, respectively). AUC and Cmax (Bartlett’s test, p = 0.004 for AUC; and Levene’s test, p = 0.042, and 0.028, respectively) This thesis has demonstrated that 1) diazepam was successfully delivered through the skin into the systemic circulation by the TDS® system, 2) novel methods have been developed for the measurement of tetracaine and its metabolite, and 3) the methods have been successfully applied to three different sample types employed in pharmacokinetic studies.

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8

Lashmar, U. T. "Vehicle effects on percutaneous absorption". Thesis, Open University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370508.

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The availability of a drug from a topical preparation is dependent on many factors, one of the most important being the composition of the vehicle. Glycerol, propylene glycol and polyethylene glycol 200 are widely used as ingredients in topical formulations. The aim of this study was to examine how these glycols affected some of the fundamental factors involved in percutaneous absorption of ethyl- methyl- and glycol salicylate. To do this, certain drug-vehicle, drug-vehicle-skin and vehicle-skin interactions were investigated. Drug-vehicle interactions were evaluated using solubility - and rheological measurements, equilibrium dialysis, diffusion coefficient - and release rate determinations. In particular, the study showed that it is important to consider the viscosity contribution of a cosolvent to the vehicle and that it is essential not to over solubilise a drug in the vehicle. The evaluation of drug-vehicle-skin interactions involved both in vitro and in vivo determinations. The in vitro study consisted of solubility- and partition coefficient measurements together with determination of diffusion coefficients and penetration rates for the drugs and the glycols using a two compartment cell in which nude mouse skin was the rate controlling barrier. In vivo, the concentrations of the glycols were determined in the individual layers in the skin and in the plasma of nude mice. The flux of the salicylates was largely unaffected by the various solvent concentrations and the different solvents, except when high concentrations of propylene glycol and glycerol were employed. The measurements of glycerol and propylene glycol in the skin and plasma suggested that the amount of the glycols penetrating into the skin from a topical application were unlikely to have any effect on the partition coefficient of a drug between the vehicle and the skin or the diffusivity of the drug in the skin phase. A comparison of the in vivo and in vitro results indicated a good correlation between these studies. In vivo and in vitro histological assessment were employed to evaluate vehicle-skin effects. Applications of glycerol and PEG 200 had no effect on the skin, whereas increasing concentrations of propylene glycol caused progressive disintegration of the stratum corneum. Some `penetration enhancers' showed unacceptable levels of skin damage and/or irritancy. Future studies may correlate these findings with their penetration enhancing properties.

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9

Hinselwood, David C. "The absorption and metabolism of cinnamic compounds in skin". Thesis, Imperial College London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501448.

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10

Jung, Connie Tom. "PERCUTANEOUS ABSORPTION OF CATECHOL IN RAT AND HUMAN SKIN". University of Cincinnati / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=ucin971368708.

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11

Hewitt, Philip Gavin. "In vitro percutaneous absorption of agrochemicals : kinetic and metabolic studies". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309132.

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12

Clark, Nicholas William Edward. "Cutaneous xenobiotic metabolism and its role in percutaneous absorption". Thesis, University of Newcastle Upon Tyne, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317857.

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13

BHATT, VARSHA DILIP. "ABSORPTION AND EVAPORATION OF PESTICIDES FROM HUMAN SKIN IN VITRO". University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1179493407.

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14

La, Count Terri D. "Skin Absorption Modeling of Metal Allergens via the Polar Pathway". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1397736577.

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15

French, Edward James. "The enhancement of percutaneous absorption by nonionic surfactants". Thesis, University of Bath, 1991. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279431.

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16

Mollee, Thomas. "Mathematical modelling of solute transport through stratum corneum /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18923.pdf.

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17

Davis, Shawn Paul. "Hollow microneedles for molecular transport across skin". Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/8055.

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18

Davis, Shawn Paul. "Hollow microneedles for molecular transport across skin". Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-06072004-131118/unrestricted/davis%5Fshawn%5Fp%5F200305%5Fphd.pdf.

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19

Supanpaiboon, Wisa. "Percutaneous absorption and metabolism of naphthalene and phenanthrene". Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364851.

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20

Keene, Warren Edward. "Evaluation of microdialysis as a tool for studying percutaneous drug absorption and cutaneous metabolism". Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268627.

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21

Selzer, Dominik [Verfasser] y Ulrich F. [Akademischer Betreuer] Schäfer. "Mathematical characterization of skin absorption / Dominik Selzer. Betreuer: Ulrich F. Schäfer". Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2016. http://d-nb.info/1090875673/34.

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22

Burch, Charmita P. "The extent of perturbation of skin models by transdermal penetration enhancers investigated by ³¹P NMR and fluorescence spectroscopy". unrestricted, 2007. http://etd.gsu.edu/theses/available/etd-04252007-133030/.

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Thesis (Ph. D.)--Georgia State University, 2007.
Title from thesis title screen. Author's name from thesis title screen. Jerry C. Smith, committee chair; Kathryn Grant, Stuart Allison, committee members. Electronic text (148 p. : ill. (some col.)) : digital PDF file. Description based on contents viewed October 5, 2007. Includes bibliographical references (p. 124-148).

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23

Tonge, Robert Patrick. "The cutaneous disposition of the sensitizing chemicals hydroxycitronellal and dinitrochlorobenzene". Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309531.

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24

Traversa, Brigette Danielle. "Enhancement of the percutaneous absorption of the opioid analgesic fentanyl". Monash University, Dept. of Pharmaceutics, 2004. http://arrow.monash.edu.au/hdl/1959.1/9597.

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25

Gonzalez, Helena. "Studies of sunscreens : percutaneous absorption of Benzophenone-3 and photostability /". Göteborg : Department of Dermatology and Venereology, Institute of Clinical Sciences, The Sahlgrenska Academy at Göteborg University, 2006. http://hdl.handle.net/2077/721.

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26

Henry, Sʹebastien. "Microfabricated device for transdermal drug delivery". Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/20707.

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27

Dick, Ian Peter. "Factors affecting the dermal absorption of lindane : the use of in vitro and in vivo techniques". Thesis, University of Newcastle Upon Tyne, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261320.

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28

Gajjar, Rachna M. "Absorption and Evaporation of Volatile Organic Solvents from Human Skin In Vitro". University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1282578243.

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29

Doran, Edward M. "Measuring and modeling dermal absorption of pesticide residues /". Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/8454.

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30

SAIYASOMBATI, PENPAN. "MATHEMATICAL MODEL FOR PREDICTING THE PERCUTANEOUS ABSORPTION OF FRANGRANCE RAW MATERIALS". University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1061561348.

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31

Williams, Daffydd Griffin. "Mechanism of action of penetration enhancers". Thesis, Cardiff University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320625.

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32

Demana, Patrick Hulisani. "Tropical corticosteroid bioequivalence testing comparison of chromameter and visual data". Thesis, Rhodes University, 1998. http://hdl.handle.net/10962/d1003233.

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The major criticism of the human skin blanching assay is the subjective nature of grading the response. Recently the American FDA released a Guidance document for topical corticosteroid bioequi valence testing. The guidelines require the use of a chromameter as a reliable method to estimate skin blanching. The purpose of this study was to evaluate the recommendations of this document for appropriateness by comparing visual and chromameter data. The visually-assessed blanching assay methodology routinely practised in our laboratories was modified to comply with the specifications of the Guidance. The preliminary trial indicated that the training period that is required for a novice to be classified as an experienced observer is not a major problem. The major trend that emerged from the pilot study was that visual assessment was better than the chromameter. Longer dose durations were found to be more discriminatory than shorter durations. The visual data were best described by the sigmoid Emax model and the chromameter data were best described by the simple Emax model. The pivotal results indicated that the D2/Dj criterion to determine sample size of "acceptable blanchers" produced only few subjects suggesting that the validity of this criterion requires extensive investigations. The estimates of the Locke's confidence interval method were simiJar to those for the general simple formula. However, due to undefined parameters of the Locke's method in the Guidance, the validity of the Locke's method requires evaluation. The chromameter b-scale parameter was the least sensitive in estimating skin blanching whereas the a- and L-scale parameters produced similar results. Poor correlation between visual and chromameter was noted indicating that the visual method is still the best method.

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33

Roper, Clive Steven. "In vitro approaches to the prediction of percutaneous absorption and metabolism : a study of ethoxylates". Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359002.

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34

Ashrafi, Parivash. "Predicting the absorption rate of chemicals through mammalian skin using machine learning algorithms". Thesis, University of Hertfordshire, 2016. http://hdl.handle.net/2299/17310.

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Machine learning (ML) methods have been applied to the analysis of a range of biological systems. This thesis evaluates the application of these methods to the problem domain of skin permeability. ML methods offer great potential in both predictive ability and their ability to provide mechanistic insight to, in this case, the phenomena of skin permeation. Historically, refining mathematical models used to predict percutaneous drug absorption has been thought of as a key factor in this field. Quantitative Structure-Activity Relationships (QSARs) models are used extensively for this purpose. However, advanced ML methods successfully outperform the traditional linear QSAR models. In this thesis, the application of ML methods to percutaneous absorption are investigated and evaluated. The major approach used in this thesis is Gaussian process (GP) regression method. This research seeks to enhance the prediction performance by using local non-linear models obtained from applying clustering algorithms. In addition, to increase the model's quality, a kernel is generated based on both numerical chemical variables and categorical experimental descriptors. Monte Carlo algorithm is also employed to generate reliable models from variable data which is inevitable in biological experiments. The datasets used for this study are small and it may raise the over-fitting/under-fitting problem. In this research I attempt to find optimal values of skin permeability using GP optimisation algorithms within small datasets. Although these methods are applied here to the field of percutaneous absorption, it may be applied more broadly to any biological system.

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35

Tarnowska, Malgorzata. "Evaluation of skin absorption of inorganic ions with regard to their physicochemical properties". Thesis, Lyon, 2019. https://n2t.net/ark:/47881/m6vm4bkz.

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La peau constitue une interface unique entre l’organisme et son environnement extérieur. Son rôle principal est de protéger les organes internes contre les facteurs externes. Le stratum corneum, est la couche supérieure et très hydrophobe de la peau. Elle était considérée peu perméable pour les molécules hydrophiles chargées tels que les ions inorganiques. Plusieurs études ont démontré le contraire et l’étude récente par Paweloszek et al. a indiqué l’importance du transport actif dans le passage cutanée des ions halogénures. L’absorption cutanée des ions classés selon la série de Hofmeister (F-, Br-, I-, SCN, ClO4-) seuls et en mélanges bi- et ternaires a été évaluée dans deux séries d’expériences in vitro. Tous les ions ont pénétré dans la peau viable en 24h. Parmi les halogénures, la presence de F- a diminué l’absorption de Br- et de I- en mélanges, tandis qu’une synergie d’absorption entre Br- et I- a été observée. Dans le second groupe (I-, SCN-, ClO4-), la pénétration cutanée du ClO4- a été inhibé par la présence des autres ions. L’impact de la formulation sur l’absorption cutanée de Ca2+ et Mg2+ présents dans des eaux thermales (TSW) a été évaluée. Différentes formes galéniques telles que des émulsions (TSW/O, O/TSW, TSW/O/W) et des liposomes ont été étudiées. Les liposomes et les émulsions ont favorisé la rétention de ces ions d’intérêt dans les couches cutanées en comparaison à l’eau themale pure. Nos résultats ont démontré que les effets bénéfiques associés aux traitements à base de TSW ne sont pas seulement dus à une action superficielle mais à la pénétration des ions dans la peau. Dans cette thèse nous démontrons la capacité des anions et cations à pénétrer la peau viable in vitro et nous mettons en évidence les effets de mélange et de la formulation sur la pénétration cutanée
Human skin forms a unique interface between the body and the external environment. Its main role is to protect the internal organs from external factors. Its highly hydrophobic outermost layer, stratum corneum, has long been believed impermeable for highly hydrophilic compounds, including ions. Several studies proved this concept wrong, and recent research by Paweloszek et al. demonstrated the important contribution of facilitated transport in permeation of halide anions. Skin penetration of anions classified in Hofmeister series (of F-, Br-, I-, SCN, ClO4-) alone and in bi- and ternary mixtures in two experimental series was studied in vitro. All tested ions permeated viable skin within 24h. Among halides, the presence of F- reduced the penetration of Br- and I- in mixtures, and synergy between Br- and I- was observed. Within the second group (I-, SCN-, ClO4-) the inhibition of ClO4- penetration in the presence of other ions was observed. Finally, the impact of formulation of marketed thermal spring water (TSW) into emulsions (TSW/O, O/TSW, TSW/O/W) and liposomes on skin absorption of Ca2+ and Mg2+ was evaluated. Liposomes and emulsions promoted retention of Ca2+ and Mg2+ in skin layers as compared to TSW. Our results prove that the beneficial effects observed during treatment with TSW are associated with penetration of the minerals into and through the skin and are not only a surface action. In this thesis, we demonstrate the possibility of both anions and cations to penetrate viable skin in vitro, and we disclose the effects of mixing and formulating on skin penetration profiles

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36

Dahal, Amit. "Assessment of the Percutaneous Absorption of ABH PLO Gel Across Porcine Ear Skin". University of Toledo Health Science Campus / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=mco1533321469656146.

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37

Reed, Susan, of Western Sydney Hawkesbury University y of Science Technology and Environment College. "Development of method to assess skin contact to chemicals". THESIS_CSTE_XXX_Reed_S.xml, 2001. http://handle.uws.edu.au:8081/1959.7/611.

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Chemical exposure of the skin has become a route of entry of some chemicals into the body and has come under major review in recent times. This research aims to develop a method of estimating skin exposure that is both reliable and non-prohibitive in cost. This involved the design and testing of skin patches adaptable for monitoring skin exposure to chemicals using several different types of absorbents which could be easily worn against skin. The final design of the patch used either activated charcoal or tenax as the absorbing medium. The patches were then desorbed with a solvent in order to analyse the chemicals. The results of the study showed that many skin exposures do not have a direct relationship with inhalation exposures, which is important because currently there are no estimates of the levels of skin exposures that may have potential long term health effects. The patch has proved successful for detecting the presence and determining the amount of chemicals that come in contact with the skin. Charcoal patches have the widest application, but are not suitable for all situations and tenax should be used on these occasions.
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38

Prapopoulou, Maria. "The development of a computation/mathematical model to predict drug absorption across the skin". Thesis, King's College London (University of London), 2012. https://kclpure.kcl.ac.uk/portal/en/theses/the-development-of-a-computation--mathematical-model-to-predict-drug-absorption-across-the-skin(f82404cb-262e-49e9-af8a-b85b216f2bb8).html.

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The ability to predict accurately the dermal permeation of a chemical is important for the development of new therapeutic formulations in transdermal drug delivery and also for the assessment of the potential risks of environmental chemicals and agents used in cosmetics industry. There have been a large number of studies investigating skin permeability, both experimentally- and theoretically-based. The experimental measurement of skin permeability is a time-consuming and difficult process and, when put in the context of the great numbers of chemicals that may come into contact with the skin, it is also costly. As a consequence, there has been a great interest over the past years to 'predict' the ability of a compound to cross the skin using its physicochemical characteristics and a number of mathematical models have been reported. Most models are based on experimental data, with skin permeability linearly correlated to the physicochemical properties and/or molecular structure parameters of the chemical compounds. A multilinear regression method is often used to fit available experimental data and such empirical models are referred to as quantitative structure-property relationships (QSPRs). Many QSPR models relate skin permeability to the physicochemical properties of the solutes while others use molecular structure properties. Successful application of such models can realise a marked reduction in the number of potentially therapeutic molecules requiring synthesis and validation since they can be precluded from study on the basis of their predicted lack of skin permeability. In terms of skin permeability data with respect to QSPR analysis, the science has not been developed significanijy since the publication of what is now universally known as the Flynn dataset (Flynn 1990). The most widely cited model that was developed on the basis of the Flynn dataset was the Potts and Guy (1992) model and since then a number of alternative models have been developed using the Flynn and other subsequendy assembled datasets. The aim of this study was to determine the limitations of the existing models and to address any deficiencies by the development of new mathematical models. Databases containing measured and well-defined skin absorption data are a key first step in the development of QSPR models, which might improve the understanding of the dermal absorption process for chemicals. Therefore the first objective was to develop a more stringently controlled database that induded parameters derived under more strictly defined experimental conditions. These data could then enable the current models to be re-evaluated and accordingly a detailed analysis of all the available in vitro dermal absorption data to be conducted with a view to classifying the data according to the corresponding experimental conditions employed so as to produce a number of data subsets. Subsequendy, advanced computational regression modelling methods, such as the Gaussian method, were applied to develop the most efficient model in terms of statistical fit. The Gaussian process (GP) has not been applied previously to skin permeability data. The potential of induding additional descriptors such as molecular weight, lipophilicity, Fedors' solubility parameter, hydrogen bond acceptor and donor capacity into any developed equations with a view to improving accuracy was investigated. For comparison reasons, a new linear regression model was also developed based on the above-mentioned 5 additional descriptors (5f linear regression model). The GP model yielded a predictive model that provided a significandy more accurate estimate of skin absorption than previous models across a wider range of molecular properties. It proved to be particularly capable of providing excellent predictions where previous studies have shown QSPRs to fail: at high log P and MW of penetrants. The results indicate that, in terms of statistical performance, the Gaussian model was better than the 5f model. This suggested that, statistically, a nonlinear approach, as employed herein, is more appropriate for analysis than linear techniques. The relative accuracy of the GP, 5f linear regression and Potts and Guy (1992) models were also compared. Permeation data were obtained under carefully controlled conditions and these were correlated to values calculated from the application of various models. Apart from comparing the experimental values with those predicted from each model, all deviations were recorded and the performance of each model was assessed. The flux values of two drug candidates, ibuprofen and furosemide, determined using the GP and 5f models, agreed well with those obtained experimentally. However, procaine hydrochloride diffused at a rate that was slower than that predicted by all models and paracetamol diffused at a much higher rate than was predicted from the GP model. The latter results could possibly be due to the relatively small degree of paracetamol ionisation. As a resutt, the effect of ionisation on permeability was measured by determining the flux of a single ionisable drug at three different pH values. The experimental results obtained were compared with the linear ionisation model, in which log D values were incorporated into the equation instead of log P values. It was concluded that ionisation, together with nonlinearity, were some of the most important factors that require further consideration when designing new models to predict dermal absorption. A series of more strictly defined databases was successfully assembled during the course of this study and used to propose novel computational models for dermal absorption. Such models showed satisfactory predictive capacity but do require further development, particularly in the case of ionisable compounds. However, the development of such databases alone is of great use for future model development.

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39

Lockley, David Jason. "Percutaneous absorption and metabolism of glycol ethers : predictions by an in vitro approach". Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311131.

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40

Golmohammadi, Arash. "Percutaneous penetration of parabens through the human epidermal membrane /". [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18696.pdf.

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41

Smith, Eric W. "Aspects of the transdermal permeation and analysis of betamethasone 17-valerate". Thesis, Rhodes University, 1988. http://hdl.handle.net/10962/d1004741.

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The current world-wide interest in transdermal drug delivery makes the prospect of valid in vitro diffusion cell methodology highly attractive. A new laboratory diffusion cell has been designed and constructed based on theoretical principles and practical permeation reports surveyed in recent literature, and has been applied to the monitoring of betamethasone 17-valerate permeation. The cell performance has been validated with respect to hydrodynamic mixing efficiency and temperature of the receptor phase. The steady-state permeation of this corticosteroid has been monitored through various synthetic and animal membranes in order to select the most appropriate media for in vitro study. The permeation of betamethasone 17-valerate has been monitored from various types of commercial and extemporaneously prepared semisolid topical formulation (cream, lotion, ointment and scalp application), through silicone membrane, human and weanling pig stratum corneum, and full thickness hairless mouse skin, and these in vitro results have been compared to data from in vivo blanching assays, using the same formulations, in an attempt to correlate the findings. This experimental methodology has necessitated the development of ancillary analytical techniques. A column-switching high-performance liquid chromatographic method has been developed for the rapid on-line clean-up and analysis of betamethasone 17-valerate contained in the various topical formulations, which minimizes sample handling and extraction procedures. The method has been modified for the analysis of this corticosteroid in the isopropyl myristate receptor phase used in the in vitro permeation experiments, and scintillation counting of tritium-labelled water has been used to verify the integrity of the animal membranes. The comparison of in vitro permeation and in vivo blanching results indicate good correlation of the data in certain instances. The closest correlations have been observed when the human stratum corneum has been used in vitro and these results are compared to data from the occluded mode of the blanching assay. The results of the porcine and murine media have also correlated with the human in vivo data, whereas the silicone membrane appears applicable only in certain in vitro experiments. The results indicate that valid, comparative percutaneous absorption data may be obtained in vitro by using a well designed, validated diffusion cell system.

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42

Pefile, Sibongile C. "A study of the transdermal drug diffusion properties of rooperol tetra-acetate". Thesis, Rhodes University, 1998. http://hdl.handle.net/10962/d1007649.

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The rapidly growing interest in the potential use of topical drug delivery formulations has resulted in increased use of the skin as a vital port for drug delivery. Extensive research has been conducted in designing vehicles capable of delivering a desired amount of drug to a specific site, to produce the desired pharmacological response. Rooperol tetra-acetate is a lipophilic, cytotoxic drug with the potential for use in the treatment of solar keratosis. For effective pharmacological action, delivery of the drug to the epidermal/dermal junction of the skin is required. A study of the topical penetration properties of rooperol tetra-acetate from different topical bases, each possessing different physico-chemical properties, was performed. The assessment involved a comparison of the diffusion properties under occlusive and non occlusive conditions when the drug was formulated into a gel, Cetomacrogol Cream B.P. (oil-inwater), Simple Ointment B.P. and an extemporaneously prepared water-in-oil topical cream. The in vitro experiments were conducted using polydimethylsiloxane and rat membrane mounted in a Franz diffusion cell. The topical permeation kinetics of rooperol tetra-acetate were determined by exploring the release characteristics of the active ingredient from the vehicles formulated and the permeability properties of the drug through the membranes employed. Further studies involved investigating the utilization of supersaturated systems intended to increase the thermodynamic activity of the drug when formulated into a propylene glycol/water vehicle (with and without polymer). To measure the release of rooperol tetra-acetate into the skin from a topical base it was necessary to, firstly, develop a suitable quantitative method for the analysis of the active drug in the aqueous receptor phase of in vitro diffusion cells. The second stage of product development was the design of an effective delivery system to facilitate the release of the diffusant from its base. A high performance liquid chromatographic method was utilized for the identification and quantification of the active drug. As validation is an important aspect in the development and subsequent utilization of an analytical procedure, the developed HPLC technique was validated by determining the precision, accuracy, range, limit of quantitation and sensitivity of the system. Lastly, the stability of rooperol tetra-acetate at elevated temperatures was assessed and a stability profile of the drug was generated for the three-month period of analysis. The results obtained following chromatographic analysis of the receptor phase sampled during the diffusion experiments indicate that the gel and oil-in-water formulations most effectively promoted the diffusion of rooperol tetra-acetate across polydimethylsiloxane membrane. The water-in-oil system exhibited lower flux rates and the ointment showed the least drug release. Occlusion of the topical vehicle increased the diffusitivity of the permeant from all formulations analysed. The permeation assessment results of the supersaturated systems showed enhanced diffusion of rooperol tetra-acetate across polydimethylsiloxane and rat membrane. The high thermodynamic activity existing in supersaturated systems most effectively increased the driving force for drug diffusion resulting in enhanced percutaneous penetration of rooperol tetra-acetate beyond the release and transport limitations of saturated solutions. These results provide the basis on which an effective topical drug delivery vehicle may be designed for this new drug entity.

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43

SANTHANAM, ARJUN. "MATHEMATICAL MODEL TO PREDICT THE SKIN DISPOSITION OF DEET AND OTHER VOLATILE COMPOUNDS". University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1092343602.

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Karr, Jennifer I. "A novel encapsulation favorably modifies the skin disposition of topically-applied N,N-diethyl-3-methylbenzamide (DEET)". University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1353154812.

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Reed, Susan. "Development of method to assess skin contact to chemicals /". View thesis View thesis, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030520.115134/index.html.

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Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 2001.
A thesis presented in fulfilment of the requirement for the degree of Doctor of Philosophy, College of Science, Technology and Environment, University of Western Sydney, Richmond, April 2001. Bibliography : leaves 138-148.

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46

Ray, Chaudhuri Siladitya. "Mathematical Modeling of Percutaneous Absorption of Volatile Solvents Following Transient Liquid-Phase Exposures". University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1179468433.

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LIMA, CASSIO A. "Caracterização bioquímica de lesões neoplásicas via espectroscopia de absorção no infravermelho por transformada de Fourier". reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/23986.

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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-10-22T16:48:07Z No. of bitstreams: 0
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Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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48

CARDOSO, TALITA R. "Aplicabilidade de curativos a base de hidrogel com nanopartículas de prata em lesão por pressão". reponame:Repositório Institucional do IPEN, 2017. http://repositorio.ipen.br:8080/xmlui/handle/123456789/27972.

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Submitted by Marco Antonio Oliveira da Silva (maosilva@ipen.br) on 2017-11-09T11:05:48Z No. of bitstreams: 0
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Cuidar de feridas é um processo dinâmico e complexo que requer atenção especial principalmente quando se refere a uma lesão crônica. A lesão por pressão (LPP) é uma ferida crônica localizada na pele ou no tecido subjacente, geralmente sobre uma proeminência óssea, resultante de pressão isolada ou pressão combinada com fricção ou cisalhamento. O objetivo foi avaliar a aplicabilidade das membranas de hidrogel com nanopartículas de prata no tratamento de lesões por pressão (LPPs) em usuários do SUS, por meio de protocolo clínico. O projeto da pesquisa foi aprovado pelo Comitê de Ética em Pesquisa da UFT/TO sob nº 161/2013, e foram seguidos todos os preceitos éticos conforme Resolução 466/12 do CNS do Ministério da Saúde. Trata-se de um estudo de intervenção terapêutica, do tipo ensaio clínico não controlado, sobre a avaliação do uso da membrana de hidrogel com nanopartículas de prata (NPAg) produzida pelo Instituto de Pesquisa em Energia Nuclear (IPEN). A população do estudo foi composta por 19 pacientes, que por critérios de inclusão e exclusão foi constituída por uma amostra de 6 (seis) pacientes de ambos os gêneros, internados no Hospital de Referência de Porto Nacional, no período de janeiro de 2014 a dezembro de 2015, acometidos por lesões por pressão categoria 3, 4 e não classificável. O estudo apresentou como limitações o restrito número de pacientes por amostra, por se tratar de pesquisa clínica experimental, com um grupo investigado altamente selecionado pelos critérios de exclusão e inclusão. Os hidogéis com NPAg, produzidos pelo IPEN, mostraram-se eficazes no tratamento das LPPs, pois proporcionaram a ferida condições para a epitelização. Houve diminuição do odor, dos tecidos desvitalizados e da dor, itens estes que quando presentes retardam a cicatrização. Porém são necessários novos estudos, envolvendo estes curativos com um número maior de pacientes.
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

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49

Intarakumhaeng, Rattikorn. "Factors Influencing Percutaneous Absorption:Effects of Solvents, Solute Physicochemical Properties, and Penetration Enhancer". University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1491316295006087.

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Alsaab, Hashem O. "Evaluation of the Percutaneous Absorption of Chlorpromazine Hydrochloride from PLO Gels Across Porcine Ear and Human Abdominal Skin". University of Toledo Health Science Campus / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=mco1435670713.

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