Gelatin hydrogels with PAMAM nanostructured surface and high density surface-localized amino groups

Amino-terminated PAMAM dendrimers with 16 and respectively 64 amino groups have been chemically immobilized onto the surface of glutaraldehyde (abbreviated GA) crosslinked thin gelatin scaffolds based on Schiff-base linkage formation between the amines and free aldehyde from partially unreacted GA. Crosslinking and dendrimers surface modification of hydrogels have been chemically and physically investigated using FT-IR spectroscopy and microscopy, UV-VIS, LM, AFM, swelling tests and a colorimetric technique. Two types of gelatin-based hydrogels with homogeneous nanorough surfaces and presenting an increased number of amino groups available for further chemical reactions have been obtained. The synthesis strategy presented in this work seems to open a new route for nanorough crosslinked gelatin scaffolds that could be further used for biomedical and especially for hard tissue engineering application.