Porphyran capped gold nanoparticles as a novel carrier for delivery of anticancer drug: In vitro cytotoxicity study

In the present study, we have explored porphyran as a reducing agent for one pot size controlled green synthesis of gold nanoparticles (AuNps) and further investigated its application as a carrier for the delivery of an anticancer drug. The prepared AuNps showed surface plasmon resonance centered at 520 nm with average particle size of 13 +/- 5 nm. FTIR spectra suggested that the sulfate moiety is mainly responsible for reduction of chloroauric acid. The capping of the AuNps with porphyran was evident from the negative zeta potential value responsible for the electrostatic stability. Thus, porphyran acts as reducing as well as capping agent. These AuNps are highly stable in a wide range of pH and electrolyte concentration. Porphyran capped AuNps exhibited enhanced cytotoxicity on human glioma cell line (LN-229) as compared to native porphyran. Consequently, these AuNps have been utilized as a carrier for delivery of the anticancer drug doxorubicin hydrochloride (DOX). Spectroscopic examination revealed that DOX conjugated onto AuNps via hydrogen bonding. The release of DOX from DOX loaded AuNps was found to be sixfold higher in acetate buffer (pH 4.5) as compared to physiological buffer (pH 7.4). Further, the DOX loaded AuNps demonstrated higher cytotoxicity on LN-229 cell line as compared with an equal dose of native DOX solution. This established the potential of these AuNps as a carrier for anticancer drug delivery. (C) 2011 Elsevier B.V. All rights reserved.