Formulation and development of bioadhesive transdermal gel of ropivacaine loaded nanoparticles for enhancement of anesthetic effect: Preclinical study in animal model

A transdermal drug delivery system (TDDS) is one of the most attractive approaches and is popular due to high patient compliance, low risk and ease of applicability. To formulate a bioadhesive gel with Ropivacaine-loaded nanoparticles for enhancement of the local anaesthesia. The ionotropic gelation method was used to formulate nanoparticles and characterized for particle size, zeta potential, PDI, drug loading and surface morphology. The optimized nanoparticulate formulation was further used in the development of bioadhesive gel and characterized for clarity, pH, bioadhesive strength, drug content, viscosity, ex-vivo skin permeation and in vivo Tail Flick test on a rat model. Among nanoparticle formulations, NP4 formulation was found to be the ideal formulation based on Physico chemical parameters. The F6 bioadhesive gel was considered optimised amongst all the formulations. The F6 gel showed an excellent skin permeation profile over 14 hr as compared to other formulations. This formulation showed maximum anesthetic effect compared to other formulations as observed in the tail flick test. F6 formulation containing RPV nanoparticles showed 3.32 folds increase in anesthetic activity as compared to the control gel. Bioadhesive transdermal gel containing RPV nanoparticles would be a potential alternative strategy for improving the anesthetic effect.