Transdermal delivery of vancomycin hydrochloride using combination of nano-ethosomes and iontophoresis: in vitro and in vivo study

Abstract

This study aimed to evaluate transdermal delivery of vancomycin hydrochloride using the combination of ethosomes as an encapsulating vesicle and iontophoresis. Ethosomes were prepared and evaluated in terms of electrochemical stability. Cathodal iontophoresis of negatively charged ethosomes and anodal iontophoresis of free drug solution and positively charged vesicles were conducted. The effect of current mode, density, concentration of drug and ionic strength was studied. In vivo study was performed by inducing mediastinitis in Sprague-Dawley rats using methicillin-resistant Staphylococcus aureus as infected pathogen, the mean bacterial count was compared between groups of rats, one of the treated groups received drug intramuscularly while the other group received vancomycin using iontophoretic delivery of optimized ethosomal formula. Ethosomes showed efficient electrochemical stability, cathodal iontophoresis of negatively charged vesicle (F2) showed maximum transdermal flux (550 µg/cm2/h) compared to free drug solution and other ethosomal formulae, transdermal flux was reduced by altering current mode from continuous to ON/OFF mode, reducing current density and by using normal saline as drug solvent; on the other hand, flux was potentiated by increasing drug concentration from 25 to 75 mg/ml. In vivo study revealed that there was a significant difference in terms of bacterial count between untreated and treated groups, while there was no statistically significant difference between the I.M. vancomycin treatment and treatment conducted by iontophoretic delivery of vancomycin encapsulated in ethosomal formula. Combination between ethosomes and iontophoresis had succeeded in delivering vancomycin transdermally.