The invention relates to the medical
biomaterial technical field. The current product which is widely used for preventing postoperative leakage of
cerebrospinal fluid has the disadvantages of tedious operation step, expanded volume and latent
infection risk. The invention provides a preparation method for medical grade
temperature sensitive hydroxybutyl
chitosan capable of internally using, a purifying method and an application method. The
prepared material has appropriate deacetylation degree, can guarantee good
biocompatibility, and has the advantages of simple operation, complete wound enclosing, injectable performance, biodegradability and excellent plugging effect. According to the invention, a
chitosan raw material with deacetylation degree of 10-70% is prepared, then a hydroxyl butylation reaction is carried out, and a unique
temperature sensitive performance is endowed for
chitosan; and then a unique
salting out method and a
phase transition method are employed for purifying. The prepared medical grade
temperature sensitive chitosan preparation has good temperature sensitive performance, good gel resilience performance, simple usage; and good
biocompatibility and biological
mechanical property can prove that the preparation method of the medical grade temperature sensitive chitosan blocking agent used for preventing leakage of
cerebrospinal fluid has good clinical application prospect.