Controlled cross‐linking of porcine cholecyst extracellular matrix for preparing tissue engineering scaffold

Abstract Treatment with cross‐linking agents for stabilizing biomolecules is an integral step during the preparation of many extracellular matrix‐based tissue engineering scaffolds from mammalian organs. However, excess cross‐linking may cause nonavailability of biomolecules and consequent deterioration of bioinductive properties of the scaffold. The present study considered controlling the extent of cross‐linking in a porcine cholecyst extracellular matrix scaffold prepared by a nonenzymatic and nondetergent method, by ex situ incubation of the source organ in varying concentrations of neutral buffered formaldehyde (10, 4, 1 or 0%; v/v) for in situ cross‐linking of biomolecules. Reduction of the formaldehyde concentration resulted in an increase in the extent of biodegradation and a decrease in the compactness of the mesh‐like surface microarchitecture of the scaffold. Retention of collagen was maximum when treated with 10% neutral buffered formaldehyde without any variation in the content of elastin and sulphated glycosaminoglycans. Although there was a reduction in the quantity of growth factors following the cross‐linking, fibroblasts remained viable on the scaffolds. The retention of major biomolecule was maximum and autodigestion was minimum in the scaffold prepared by the ex situ treatment of cholecyst in 10% neutral buffered formalin and found suitable for preparing the tissue engineering scaffold.