OBJECTIVES

1. Congresul National de Farmacie din Romania Ed a XV-a, Iasi, sept. 2014 Characterization of different PVA film structures depending on the obtaining method Florina Crivoi, Mihaela Baican, Diana Lacatusu Universitatea de Medicina si Farmacie , Iasi OBJECTIVES MATERIALS By adding natural additives that easily decompose, for example, starch, cellulose or collagen to polyvinyl alcohol(PVA), it obtains materials with higher or controlled degradation rate. The introduction of little amounts of biopolymers (collagen, elastin, hyaluronic acid) will lead to new biomaterials with better properties especially by the point of view of biocompatibility. Polyvinyl alcohol (PVA)/polyethylene glycol (PEG) hydrogels and PVA-derived hybrid materials were successfully produced with GA (glutaraldehyde) crosslinking in nanometer-scale network. *Poly(vinyl alcohol) with number-average molecular weight: 71 000 Dalton, polymeric degree: 1600. *Hydrolysed collagen (HC), obtained by acid hydrolysis of bovine derma; type I and III collagen; it consists of a mass of peptides. *k-Elastin is a mixture of peptides with different molecular weights as 16 000, 80 000 and 120 000 Da was obtained by alkaline hydrolysis at room temperature of natural elastin. *HA has the following composition uronic acids 31.5 wt%; total nitrogen 3.7 wt% and hexozamine 28.7 wt%. IR SPECTRAL ANALYSIS • * The band that appears in the binary blend spectra at 3308 cm-1, assigned to the –OH groups, is shifted to higher values in glycosaminoglycans containing blends spectra which means stronger bond between them. • * Bands at 2943 cm-1 and 2868 cm-1 in the blends spectra assigned to C-H bond are shifted to smaller wavenumbers values in case of the acid hyaluronic containing blend. • Bands in the 2800 – 2000 cm-1 spectral region presents different forms, for each blend, that shows different chemical bonds between components. • A band at 1659 cm-1 in the binary blend spectra appears also in other spectra, and is assigned to terminal groups interactions, in shifted towards smaller wavenumbers in the case of multicomponent blends and presents the higher intensity for the proteoglycans containing blends. ADHERENCE ANALYSIS AND CELLULAR PROLIFERATION Dermal fibroblasts culture for all polymer samples, has been done at a initial cell density of 3,5x105 cells/ml. Cell proliferation degree was similar to the control one by the point of view of fibroblasts adhesion and cell viability for the blends that contain proteoglycans, PVA/ HC/ ELS/CS and PVA/ HC/ ELS/HA at 24 hours and also, after 48 hours; for the other blends proliferation degree was higher than 83%. For the PVA sample has been obtained a minim value of 82%. CONCLUSIONS • IR spectroscopy evidence specific interactions between functional groups of the blend components which determine a better compatibility. • The analysis of human dermal fibroblasts proliferation in the presence of PVA/HC/ELS blends for different culture periods evidence a cell viability over 82 % for all samples; the normal cell phenotype is retained by all fibroblasts, that indicates the absence of cytotoxic effects. Blends that contain proteoglycans show the higher biocompatibility. * H.S. Mansur, R.L. Orefice, A Mansur; Characterization of poly(vinyl alcohol)/poly(ethylene glycol) hydrogels and PVA-derived hybrids by small-angle X-ray scattering and FTIR spectroscopy, Polymer, Vol. 45, Issue 21, 29 September 2004, p. 7193–7202. * G. Paradossi, F. Cavalieri, E. Chiessi, C. Spagnoli, M.K. Cowman; Poly(vinyl alcohol) as versatile biomaterial for potential biomedical applications. Journal of materials science. Vol. 14, 2003, p. 687 – 691. REFERENCES