The study of the surface layer of 3D-matrices for tissue engineering

Abstract

Matrices fabricated by electrospinning from polycaprolactone solutions with human albumin or gelatin to 1,1,1,3,3,3-hexafluoroisopropanol have been investigated. Microstructure of matriх surface was analyzed using scanning electron microscopy. Protein distribution in the surface layer was studied by modification with N-(2-hydroxyethyl)phenazine and X-ray photoelectron spectroscopy. The protein concentration in the surface layer of matrices was up to 12 times higher than in the initial solution, and the lower the protein concentration in the solution, the higher the relative protein content is on the surface of matrices. During incubation of matrices in aqueous solutions protein concentration in the surface layer decreased by less than 10% during the first 30–60 min and remained at this level for a long time (seven days). Treatment with proteinase K resulted in about one-third decrease in protein concentration in the surface layer. Thus, both methods used in this study are applicable for analysis of the surface layer of materials fabricated by electrospinning from mixtures of synthetic and natural polymers; however, X-ray photoelectron spectroscopy appears to be a more informative and convenient method.