Injectable thermosensitive hydrogel based on chitosan and quaternized chitosan and the biomedical properties

Abstract

A novel injectable thermosensitive hydrogel (CS–HTCC/α β-GP) was successfully designed and prepared using chitosan (CS), quaternized chitosan (HTCC) and α,β-glycerophosphate (α,β-GP) without any additional chemical stimulus. The gelation point of CS–HTCC/α β-GP can be set at a temperature close to normal body temperature or other temperature above 25°C. The transition process can be controlled by adjusting the weight ratio of CS to HTCC, or different final concentration of α,β-GP. The optimum formulation is (CS + HTCC) (2% w/v), CS/HTCC (5/1 w/w) and α,β-GP 8.33% or 9.09% (w/v), where the sol–gel transition time was 3 min at 37°C. The drug released over 3 h from the CS–HTCC/α,β-GP thermosensitive hydrogel in artificial saliva pH 6.8. In addition, CS–HTCC/α,β-GP thermosensitive hydrogel exhibited stronger antibacterial activity towards two periodontal pathogens (Porphyromonas gingivalis, P.g and Prevotella intermedia, P.i). CS–HTCC/α, β-GP thermosensitive hydrogel was a considerable candidate as a local drug delivery system for periodontal treatment.