Electro-responsive polyacrylamide-grafted-gum ghatti copolymer for transdermal drug delivery application

An application of polyacrylamide-grafted-gum ghatti (PAAm-g-GGH) copolymer for transdermal delivery of an anti-psychotic drug, quetiapine fumerate triggered by electric stimulus was explored. The electro-responsive PAAm-g-GGH was prepared by free radical polymerization underneath nitrogen atmosphere subsequent to alkaline hydrolysis. The PAAm-g-GGH was used as drug reservoir gel and crosslinked films of GGH and PVA as rate controlling membranes (RCM). The reservoir gels were uniform and translucent; pH of gels was 6.56-7.06, which is in the pH range of skin and drug content was from 89.57% to 94.51%. The thickness of RCMs was 163-227 mu; thickness was increased with increased glutaraldehyde concentration and all the RCMs were permeable to water vapors. When electric stimulus was absent, a small amount of drug was permeated from the formulations, while drug conveyance was enhanced in the existence of stimulus. Drug permeation was increased with increase in electric stimulus from 2 to 8 mA. Over two fold increase in flux was observed after application of electric stimulus. Under on-off electric stimulus, faster drug permeation was seen under 'on' condition and permeation was decreased when stimulus was 'off.' Histopathology study confirmed reversible alteration of skin structure under electric stimulus.