(Copper–curcumin) β-cyclodextrin vaginal gel: Delivering a novel metal–herbal approach for the development of topical contraception prophylaxis

Abstract

Delivering a safe and effective topical vaginal contraceptive is the need of present era. We explored the potential of a metal (copper) and herbal moiety (curcumin) for this topical contraceptive prophylaxis. Complex of copper and curcumin (Cu–Cur) was synthesized and the concerns regarding its aqueous solubility was resolved by including it into the hydrophobic cavity of β-cyclodextrin (β-CD) as (Cu–Cur)CD inclusion complex. Dose assessment was made on the basis of in-vitro spermicidal assays and cell cytotoxicity studies. Finally the (Cu–Cur)CD loaded vaginal gel was prepared, characterized and evaluated for in-vitro spermicidal activity and preclinical toxicity studies. Spectral and morphological characterizations confirmed the synthesis of (Cu–Cur) and (Cu–Cur)CD inclusion complex. Spermicidal assays and Hela cell cytotoxic data revealed an optimized 1.5% (Cu–Cur)CD for further studies. 1.5% w/w (Cu–Cur)CD loaded carbopol 974p gel provided 100% motility even at 2-fold dilution and preclinical toxicity studies in Rats and Rabbits revealed its highly safe profile. The hypothesis of considering metal–herbal complex and its cyclodextrin complex has worked and the well planned strategy of including it in (β-CD) cavity provided a preeminent platform for vaginal delivery. In-vitro assays and preclinical toxicity analysis confirmed its potential to be used as highly safe and effective prophylaxis.