Thermosensitive Macroporous Cryogels Functionalized With Bioactive Chitosan/Bemiparin Nanoparticles

• DOI: 10.1002/mabi.201300184
• Publication Date: 2013-08-19T08:04:39Z
• Authors: Hazel Peniche; Felisa Reyes‐Ortega; María R. Aguilar; Gema Rodríguez; Cristina Abradelo; Luis García‐Ferná...; Carlos Peniche; Julio San Román
• Keywords: 0301 basic medicine; B-Lymphocytes; Chitosan; Tissue Engineering; Tissue Scaffolds; Acrylic Resins; Temperature; Biocompatible Materials; Fibroblasts; Heparin, Low-Molecular-Weight; Cell Line; Polymerization; Kinetics; 03 medical and health sciences; Delayed-Action Preparations; Microscopy, Electron, Scanning; Humans; Nanoparticles; Particle Size; Porosity; Cryogels; Cell Proliferation

Thermosensitive macroporous scaffolds of poly(N‐isopropylacrylamide) (polyNIPA) loaded with chitosan/bemiparin nanoparticles are prepared by the free radical polymerization in cryogenic conditions. Chitosan/bemiparin nanoparticles of 102 ± 6.5 nm diameter are prepared by complex coacervation and loaded into polyNIPA cryogels. SEM image reveal the highly porous structure of cryogels and the integration of nanoparticles into the macroporous system. Volume phase transition temperature (VPT) and total freezing water content of cryogels are established by differential scanning calorimetry, and their porosity is determined by image‐NMR. Swelling of cryogels (above and below the VPT) is highly dependent on nanoparticles concentration. In vitro release profile of bemiparin from cryogel is highly modulated by the presence of chitosan. Bemiparin released from nanoparticles preserves its biological activity, as shown by the BaF32 cell proliferation assay. Cryogels are not cytotoxic for the human fibroblast cells and present excellent properties for application on tissue engineering and controlled release of heparin.