Clinical Pharmacology & Biopharmaceutics
Open Access

Abstract

The objective of the present study was to synthesize and characterize Cysteamine conjugated �?�?�?²-Cyclodextrin (�?�?�?²-CD-Cys) as a novel muco-adhesive polymeric excipient for vaginal drug delivery. Increasing concentrations of cysteamine (0.25%, 0.5% and 0.75%) were covalently attached to oxidized �?�?�?²-CD via reductive amination. Quantification of immobilized thiol groups through Ellmans test revealed 851.84�?�?�?±107 �?�?�?¼mol/g, 1040.44�?�?�?±132 �?�?�?¼mol/g and 1563.72�?�?�?±171 �?�?�?¼mol/g of free thiol groups attached to the polymer backbone, respectively. Viability studies of thiolated derivatives of �?�?�?²-CD at concentrations of 0.5% (m/v) showed no toxic effects on Caco-2 cells within 72 hours. Solubility of thiolated �?�?�?²-CD was furthermore 3.5-fold improved in comparison to unmodified �?�?�?²-CD. Thiolated derivatives of �?�?�?²-CD (�?�?�?²-CD-Cys851, �?�?�?²-CD-Cys1040 and �?�?�?²-CD-Cys1563) showed 3, 12.47 and 32.13-fold improved mucoadhesive properties on porcine intestinal mucosa and 5.84, 15.95 and 17.14-fold improved muco-adhesive properties on porcine vaginal mucosa, respectively. Inclusion complexes of antiviral drug acyclovir with thiolated �?�?�?²-CD resulted in increased drug solubility. According to these results, thiolated �?�?�?²-CD might be a promising novel tool for vaginal delivery of poorly water soluble therapeutic agents, such as acyclovir.

Biography

Muhammad Ijaz is a PhD student at the University of Innsbruck Austria. He did his Master of Philosophy (Pharmaceutics) from The Islamia University of Bahawal Pur and secured an Outstanding Research Scholarship for PhD from Higher Education Commission of Pakistan (HEC). He has published a review article on pre-activated thiomers in reputed journals of Expert Opinion on Drug Delivery and is currently working on various projects of advanced drug delivery systems using thiolated polymers.

Email: Muhammad.Ijaz@student.uibk.ac.at