Topical nanoemmigel formulation of boswellia serrata

Abstract

Boswellia serrata was formulated as topical analgesic and antiinflammatory nanoemmigel, which is a combination of a nanoemulsion and a nanomicellar system in a gel base. Nanoemulsion was formulated by microemulsion-template method by using probe sonication at 5 amp for 5 min. Particle size of nanoemulsion was found to be 141 nm and polydispersity index of 0.333. Nanomicelle was formulated at a ratio 1:1 of drug and surfactant and 1:10 of solvent and antisolvent using solvent evaporation method. The particle size and polydispersity index of the nanomicelle was found to be 31.07 nm and 0.205, respectively. Nanoemmigel was prepared by combining nanoemulsion and nanomicelle in the ratio 1:1 with carbopol 974 as a gelling agent. The nanoemmigel prepared was a buff coloured, opaque gel with smooth texture and good spreadability. Viscosity and drug content of the nanoemmigel was 50720 cps and 103±1.08 %, respectively. In vitro diffusion study of nanoemmigel showed 98.52±1.53 % drug permeation at the end of 5 h. The drug release mechanism of the nanoemmigel formulation can be explained using the Higuchi model. The steady state flux and permeability co-efficient of the nanoemmigel was found to be better than each of nanoemulsion gel and nanomicellar gel due to the utilization of both the pathways available to the drug for permeation through the skin. Improved therapeutic response was obtained as compared to nanoemulsion gel, nanomicellar gel, emulgel and also marketed topical product of Boswellia when examined for in vivo antiinflammatory and analgesic activity in animal models.