Microwave: Effects and Implications in Transdermal Drug Delivery

Abstract

Abstract-This study investigated transdermal drug delivery mechanisms of pectin and pectin-oleic acid (OA) gels and their effects on skin barrier treated by microwave. Hydrophilic pectin-sulphanilamide gels, with or without OA penetration enhancer, were subjected to drug release and skin permeation studies. The skins were untreated or microwave-treated, and characterized by infrared spectroscopy, raman spectroscopy, thermal, electron microscopy and histology techniques. Unlike solid film, skin treatment by microwave at 2450 MHz demoted drug permeation especially from OA-rich pectin gel. The pectin-skin binding was facilitated by gel with freely soluble pectin molecules instead of solid film with entangled chains. It was promoted when microwave fluidized stratum corneum into structureless domains, or OA extracted endogenous lipid fraction and formed separate phases within intercellular lipid lamellae. This led to a remarkable decrease in transdermal drug permeation. Microwave-enhanced transdermal delivery must not be implemented with pectin gel. In skin treated by microwave, the penetration enhancer in gel can act as a permeation retardant.

Formulation of Microwave-Assisted Natural-Synthetic Polymer Composite Film and Its Physicochemical Characterization

“…Microwave has been used in food processing [42], muscle and tendon injury treatments [43], and endometrial ablation [44]; as a transdermal permeation enhancer [45] and synthesis of carbon nitride dots from folic acid for cell imaging [46]; and for catalyzing proteolytic reactions [47] and enhancing skin drug retention for the local treatment of skin pathologies [48][49][50]. Microwave has been explored for cross-linking of polymers to prepare the polymeric microspheres [51], graft polymer synthesis for colon drug delivery [52], for hydrogel synthesis [53], as microwave coagulation treatment [53,54], for tumor cell ablation [55,56] and endometrial ablation [57,58], and for transdermal penetration of drugs [59].…”