title: DFT:B3LYP/3-21G theoretical insights on the confocal Raman experimental observations in skin dermis of healthy young, healthy elderly, and diabetic elderly women.
abstract: In the confocal Raman spectra of skin dermis, the band area in the spectral region of proline and hydroxyproline varies according to the age and health condition of the volunteers, classified as healthy young women, healthy elderly women, and diabetic elderly women. Another observation refers to the intensity variation and negative Raman shift of the amide I band. To understand these effects, we adopted a model system using the DFT/B3LYP:3-21G procedure, considering the amino acid chain formed by glycine, hydroxyproline, proline, and alanine, which interacts with two and six water molecules. Through these systems, polarizability variations were analyzed to correlate its values with the observed Raman intensities of the three groups of volunteers and to assign the vibrational spectra of the skin dermis. As a way to correlate other experimental trends, we propose a model of chemical reaction of water interchange between the bonding amino acids, in which water molecules are attached with glucose by hydrogen bonds. The theoretical results are in accordance with the observed experimental trends.
authors.affiliation: University of Paraiba Valley, Institute of Research and Development, Laboratory of Biomedical Vibrational Spectroscopy, São José dos Campos, 12244-000 São Paulo, Brazil.
authors.forename: Claudio Alberto
authors.initials: CA
authors.lastname: Téllez Soto
authors.affiliation: University of Paraiba Valley, Institute of Research and Development, Laboratory of Biomedical Vibrational Spectroscopy, São José dos Campos, 12244-000 São Paulo, Brazil.
authors.forename: Liliane
authors.initials: L
authors.lastname: Pereira
authors.affiliation: University of Paraiba Valley, Institute of Research and Development, Laboratory of Biomedical Vibrational Spectroscopy, São José dos Campos, 12244-000 São Paulo, Brazil.
authors.forename: Laurita
authors.initials: L
authors.lastname: Dos Santos
authors.affiliation: University of Paraiba Valley, Institute of Research and Development, Laboratory of Biomedical Vibrational Spectroscopy, São José dos Campos, 12244-000 São Paulo, Brazil.
authors.forename: Ramu
authors.initials: R
authors.lastname: Rajasekaran
authors.affiliation: University of Paraiba Valley, Institute of Research and Development, Laboratory of Biomedical Vibrational Spectroscopy, São José dos Campos, 12244-000 São Paulo, Brazil.
authors.forename: Priscila
authors.initials: P
authors.lastname: Fávero
authors.affiliation: University of Paraiba Valley, Institute of Research and Development, Laboratory of Biomedical Vibrational Spectroscopy, São José dos Campos, 12244-000 São Paulo, Brazil.
authors.forename: Airton Abrahão
authors.initials: AA
authors.lastname: Martin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000032:analysis / Q000737:chemistry; D020405:Dermis / Q000737:chemistry / Q000000981:diagnostic imaging* / Q000378:metabolism; D003920:Diabetes Mellitus / Q000378:metabolism*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008958:Models, Molecular; D008962:Models, Theoretical; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013816:Thermodynamics; D055815:Young Adult
chemical_list: D000596:Amino Acids