Formulation Design and Functional Characterisation of a Novel Vaginal Mucosal Drug Delivery System

The aim of this research wasthe development, characterisation, and optimisation of composite polymer-basedformulations for vaginal drug delivery using metronidazole (MTz) as a modeldrug to treat bacterial infection in the vagina. Blank (BLK) composite waferscomprising carrageenan (CARR) and sodium alginate (SA) were initiallyformulated and tested. However, due to poor physico-chemical properties,further formulations were developed involving combination of carbopol (CARB)with SA or CARB with CARR, modified with hydroxypropylmethyl cellulose (HPMC)in different weight ratios and plasticised with polyethylene glycol (PEG 200).Drug loaded (DL) wafers were obtained by loading selected optimised compositeCARB-CARR or CARR-SA based gels with 0.75% of MTz prior to freeze-drying.Formulations were characterised using texture analyser (hardness,mucoadhesion), scanning electron microscopy (SEM), X-ray diffractometry (XRD), swellingcapacity and in vitro drug dissolution study using HPLC.