Synthesis, characterization of ultrasmall gold nanocluster conjugated with Gemcitabine for anticancer activity.

The development of effective drug delivery strategy by employing novel nano-careers are advantageous for targeted and controlled drug release. The present work describes about such a strategy in the form of a protein stabilized ultrasmall gold nanocluster as nano-career for the delivery of anticancer drug Gemcitabine (Gem). Gold nanocluster (AuNCs) stabilized by bovine serum albumin (BSA) was synthesized and characterized in detail including its stability, size distribution, toxicity, and photo-physical properties. It was revealed that monodispersed gold particles (~ 1.5 nm) dispersible in aqueous phase with unique optical absorption and emission characteristics (λabs = 450 nm, λemi = 650 nm), high stability and minimum toxicity was obtained. Afterward, an anticancer drug (Gem) was conjugated with the gold cluster through simple chemical mixing resulting in the formation of 55% drug load Au nanocluster (Gem-AuNCs-BSA). The resultant Gem-AuNCs-BSA showed enhanced delivery of drug and therapeutic effects for the treatment of breast cancer and lung cancer with better efficacy than free Gemcitabine.