scholarly journals ATR-FTIR, FT-NIR and near-FT-Raman spectroscopic studies of molecular composition in human skinin vivoand pig ear skinin vitro

2008 ◽  
Vol 22 (6) ◽  
pp. 437-457 ◽  
Author(s):  
Tanja M. Greve ◽  
Kristine B. Andersen ◽  
Ole F. Nielsen

ATR-FTIR, FT-NIR and near-FT-Raman spectroscopy were used to characterize the molecular composition of human skinin vivoand pig ear skinin vitro. Due to different measurement depths the spectroscopic techniques reveal the characteristics of different layers of the skin. Tape stripping was used with the ATR-FTIR technique. Spectral differences concerning lipid content and conformation, protein secondary structure or content of water were found with respect to both gender and species (i.e. human versus pig ear) at all measured skin depths. New assignments of so far unassigned lipid and protein peaks in the FT-NIR and ATR-FTIR spectra of skin were made. PCA and PLS models were used to investigate the division of the recorded spectra into groups. With respect to classification of male and female subjects, the PLS discriminant analysis provided a classification accuracy of 64–93% based on the ATR-FTIR spectra and 83–89% based on the Raman spectra. With respect to classification of human skinin vivoand pig ear skinin vitro, the PLS discriminant analysis provided a classification accuracy of 75–100% based on the Raman spectra and 100% based on the ATR-FTIR spectra.

2021 ◽  
Vol 2127 (1) ◽  
pp. 012065
Author(s):  
I Matveeva ◽  
Y Khristoforova ◽  
A Moryatov ◽  
O Myakinin ◽  
I Bratchenko ◽  
...  

Abstract The main purpose of the paper is classification of the human skin Raman spectra using partial least squares discriminant analysis (PLS-DA) into classes depending on the disease. In vivo Raman spectra of normal skin, basal cell carcinoma, malignant melanoma and pigmented nevus are considered. A feature of the approach is the analysis not of the Raman spectra themselves, but of the concentrations of the eight most significant spectra components identified using multivariate curve resolution (MCR). As a result, the ROC curve was calculated and the optimal classification threshold was chosen. The accuracy of the classification models ranged from 63.3 to 86.7%, depending on the model. The findings suggest that this approach could also be useful for classification of specific diseases.


1996 ◽  
Vol 24 (3) ◽  
pp. 325-331
Author(s):  
Iain F. H. Purchase

The title of this paper is challenging, because the question of how in vitro methods and results contribute to human health risk assessment is rarely considered. The process of risk assessment usually begins with hazard assessment, which provides a description of the inherent toxicological properties of the chemical. The next step is to assess the relevance of this to humans, i.e. the human hazard assessment. Finally, information on exposure is examined, and risk can then be assessed. In vitro methods have a limited, but important, role to play in risk assessment. The results can be used for classification and labelling; these are methods of controlling exposure, analogous to risk assessment, but without considering exposure. The Ames Salmonella test is the only in vitro method which is incorporated into regulations and used widely. Data from this test can, at best, lead to classification of a chemical with regard to genotoxicity, but cannot be used for classification and labelling on their own. Several in vitro test systems which assess the topical irritancy and corrosivity of chemicals have been reasonably well validated, and the results from these tests can be used for classification. The future development of in vitro methods is likely to be slow, as it depends on the development of new concepts and ideas. The in vivo methods which currently have reasonably developed in vitro alternatives will be the easiest to replace. The remaining in vivo methods, which provide toxicological information from repeated chronic dosing, with varied endpoints and by mechanisms which are not understood, will be more difficult to replace.


1989 ◽  
Vol 8 (5) ◽  
pp. 853-859 ◽  
Author(s):  
Ronald C. Wester ◽  
Howard I. Maibach

Contaminants exist in ground and surface water. Human skin has the capacity to bind and then absorb these contaminants into the body during swimming and bathing. Powdered human stratum corneum will bind both lipid-soluble (alachlor, polychlorinated biphenyls [PCBs], benzene) and water-soluble (nitroaniline) chemicals. In vitro (human skin) and in vivo (Rhesus monkey) studies show that these chemicals readily distribute into skin, and then some of the chemical is absorbed into the body. Linearity in binding and absorption exists for nitroaniline over a 10-fold concentration range. Multiple exposure to benzene is at least cumulative. Binding and absorption can be significant for exposures as short as 30 min, and will increase with time. Absorption with water dilution increased for alachlor, but not for dinoseb. Soap reversed the partitioning of alachlor between human stratum corneum and water. The PCBs could be removed from skin by soap and water (70% efficiency) for up to 3 h and then decontamination potential decreased, due to continuing skin absorption. The model in vitro and in vivo systems used should permit easy estimation of this area of extensive human exposure effect on risk assessment.


2017 ◽  
Vol 309 (4) ◽  
pp. 275-283 ◽  
Author(s):  
Wen-Hwa Li ◽  
Heng-Kuan Wong ◽  
José Serrano ◽  
Manpreet Randhawa ◽  
Simarna Kaur ◽  
...  
Keyword(s):  

2016 ◽  
Vol 32 (3) ◽  
pp. 723-738 ◽  
Author(s):  
Chi-Chuan Li ◽  
Fu-Shun Yu ◽  
Ming-Jen Fan ◽  
Ya-Yin Chen ◽  
Jin-Cherng Lien ◽  
...  

1988 ◽  
Vol 94 (3) ◽  
pp. 773-780 ◽  
Author(s):  
R.M. Barr ◽  
O. Koro ◽  
D.M. Francis ◽  
A. Kobza Black ◽  
T. Numata ◽  
...  

Pharmaceutics ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 310 ◽  
Author(s):  
Stella Zsikó ◽  
Kendra Cutcher ◽  
Anita Kovács ◽  
Mária Budai-Szűcs ◽  
Attila Gácsi ◽  
...  

The aim of this research was to investigate the stability of a lidocaine-loaded nanostructured lipid carrier dispersion at different temperatures, formulate a nanostructured lipid carrier gel, and test the penetration profile of lidocaine from the nanostructured lipid carrier gel using different skin penetration modeling methods. The formulations were characterized by laser diffraction, rheological measurements and microscopic examinations. Various in vitro methods were used to study drug release, diffusion and penetration. Two types of vertical Franz diffusion cells with three different membranes, including cellulose, Strat-M®, and heat separated human epidermis were used and compared to the Skin-parallel artificial membrane permeability assay (PAMPA) method. Results indicated that the nanostructured lipid carrier dispersion had to be gelified as soon as possible for proper stability. Both the Skin-PAMPA model and Strat-M® membranes correlated favorably with heat separated human epidermis in this research, with the Strat-M® membranes sharing the most similar drug permeability profile to an ex vivo human skin model. Our experimental findings suggest that even when the best available in vitro experiment is selected for modeling human skin penetration to study nanostructured lipid carrier gel systems, relevant in vitro/in vivo correlation should be made to calculate the drug release/permeation in vivo. Future investigations in this field are still needed to demonstrate the influence of membranes and equipment from other classes on other drug candidates.


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