Polymeric hydrogel containing lidocaine loaded polyelectrolyte complex for dry socket wound dressin

Abstract

This study aimed to invent a thermoresponsive hydrogel containing lidocaine hydrochloride (LH) loaded in polyelectrolyte complex (PEC) used in dry socket wound treatment. The PEC, composed of chitosan (CS)–pectin (PC)–hyaluronic (HA), was created by varying the ratio of LH and HA according to 23 full factorial experiments. Nine formulations (LC) were assessed, and their physicochemical properties and in vitro cytotoxicity were determined. The results showed that the ratio of CS:PC:HA affected particle size, zeta potential, %entrapment efficiency, and cytotoxicity of the LC formulation. The ratio of 0.3:0.1:1.5 and 10% LH provided suitable characteristics of the PEC and was chosen for further investigation. The LC was incorporated into thermoresponsive gel formed from poloxamer407 (P407) in a ratio of 1:1. The effects of LH concentration loaded in PEC were observed in comparison to the LH in P407. All formulations observed that the gelation temperature was in the range of 27-28oC and the gelation time around 2-3 min which is all accepted range in dental routine work. The gels provided good characterization and texture profile analysis which revealed the gel hardness associated with the syringeability, and mucoadhesion. Rheology showed a pseudo-plastic flow behavior, and the LH released from hydrogel indicated sustained drug release by polymeric matrix drug delivery. The gels were 50% degraded in artificial saliva within 48 hours implying biodegradability. The hydrogel provided significantly faster onset and higher pain score reduction compared to standard benzocaine gel in clinical trials without allergy or other side effects. The LHloaded PEC in the thermoresponsive gel was successfully developed, which could be further used in a dental application.