Cell immobilization in gelatin-hydroxyphenylpropionic acid hydrogel fibers.
ABSTRACT Gelatin-hydroxyphenylpropionic acid (Gtn-HPA) hydrogels are highly porous and biodegradable materials. Herein we report a fiber spinning method that can produce cell-seeded solid and hollow hydrogel fibers by enzymatically cross-linking Gtn-HPA in solutions flowing within a capillary tube. The cell-immobilized hydrogel fibers, with feature sizes down to 20 microm, are formed as a result of continuous cross-linking of cell-mixed hydrogel precursors in a multiphase laminar flow. This fiber formation process is mild enough to retain the cell viability. The continuous fiber formation, simultaneous cell encapsulation, as well as versatile combination of fiber structures provided by this approach make it a promising and effective technique for the preparation of cell-seeded hydrogel scaffolds and carriers for tissue engineering.
Article: A Multi-Layered Scaffold of A Chitosan and Gelatin Hydrogel Supported by A Pcl Core for Cardiac Tissue Engineering.[show abstract] [hide abstract]
ABSTRACT: A three-dimensional scaffold comprised of self-assembled polycaprolactone (PCL) sandwiched in a gelatin-chitosan hydrogel was developed for use as a biodegradable patch with a potential for surgical reconstruction of congenital heart defects. The PCL core provides surgical handling, suturability and high initial tensile strength, while the gelatin-chitosan scaffold allows or cell attachment with pore size and mechanical properties conducive to cardiomyocyte migration and function. The ultimate tensile stress of the PCL core, made from blends of 10, 46 and 80 kDa (Mn) PCL, was controllable in the range of 2-4 MPa, with lower average molecular weight PCL blends correlating with lower tensile stress. Blends with lower molecular weight PCL also had faster degradation (controllable from 0-7% weight loss in saline over 30 days) and larger pores. PCL scaffolds supporting a gelatin-chitosan emulsion gel showed no significant alteration in tensile stress, strain or tensile modulus. However the compressive modulus of the composite tissue was similar to that of native tissue (∼ 15 kPa for 50% gelatin and 50% chitosan). Electron microscopy revealed that the gelatinchitosan gel had a 3-D porus structure with a mean pore diameter of ∼ 80 μm, migration of neonatal rat ventricular myocytes (NRVM), maintained NRVM viability over 7 days, and resulted in spontaneously beating scaffolds. This multi-layered scaffold has sufficient tensile strength and surgical handling for use as a cardiac patch, while allowing migration or pre-loading of cardiac cells in a biomimetic environment to allow for eventual degradation of the patch and incorporation into native tissue.Acta biomaterialia 11/2012; · 3.98 Impact Factor