Preparation of chitosan–gelatin scaffold containing tetrandrine-loaded nano-aggregates and its controlled release behavior

Abstract A well-timed delivery of bioactive macromolecules from the porous scaffolds is very important in tissue engineering. Tetrandrine (Ted) is one of a large number of known plant derived bisbenzylisoquinoline alkaloids and is obtained from the roots of Stephania tetrandria . Ted can be used as a modifier to poly( l -lactic acid) scaffolds to promote chondrocyte differentiation and secrete type II collagen. But the effect of Ted on chondrocyte's behavior strongly depends on the concentration of Ted in the culture media. Here amphiphilic diblock copolymer (PLAE) composed of l -lactide and methoxy poly(ethylene glycol) (MePEG) was prepared and the Ted loaded copolymeric nanospheres were obtained by self-emulsification and then solvent evaporation. The mean sizes of core/shell type PLAE nanospheres and Ted-loaded nanospheres are about 60 and 100 nm, respectively. Chitosan–gelatin (Cs–Gel) porous scaffolds loaded with PLAE–Ted nanospheres were fabricated through freeze drying. Ted release behaviors from PLAE–Ted nanospheres and porous scaffolds were investigated. The result shows that the Ted-loaded nanospheres could be embedded within Cs–Gel scaffolds and no initial burst release could be observed in the release patterns. Here a room can be provided for the scaffolds to sustained release bioactive component in tissue engineering.