Preparation of polylactic acid/chitin composite material and its safety evaluation by animal experiments.

Objective: To prepare a scaffold material with good biocompatibility and biodegradability by compounding polylactic acid (PLA) and chitin.

Methods: After preparation of PLA from lactic acid, the compounding of PLA and chitin was carried out by dissolving these 2 materials in one solution for reaction. The composite material was obtained and molded after the solvent was evaporized, and the safety tests of this resultant material were conducted in guinea pigs and New Zealand rabbits, respectively.

Results: In allergic test, the guinea pigs responded to the digestion solution of the composite material in almost the same manner as to normal saline (the latter serving as negative control), and no obvious allergic reaction was observed in the animals except those in positive control group. Pyrogenic test by injecting the digestion solution of the composite material in 6 rabbits found a raise in the body temperature less than 0.2 degrees Celsius, with the total increase (adding up the individual temperature raise) less than 1.0 degrees Celsius, to meet the accepted criteria for the pyrogenic test. In subsequent toxicity test, the rabbits showed no signs of agitation or inanimate behavior after injection.

Conclusions: PLA/chitin composite material conforms to the ISO10993-1, and can be used as a basic scaffold material in tissue engineering.