The effects of conjugating anti-MUC1 aptamers on gold nanobipyramids and nanostars for photothermal cancer ablation

<b>Aim:</b> To ascertain the impact of shape and surface modification of anisotropic nanoparticles on the toxicity and photothermal efficiency toward cancerous cell lines. <b>Methods:</b> Gold nanobipyramids and nanostars surface modified with MUC1 aptamer were used in the current study to explore the toxicity and photothermal efficiency on MCF7 breast cancer cell lines via MTT assay. <b>Results:</b> Surface functionalization with MUC1 aptamer showed significant reduction in % cytotoxicity and increase in % specific internalization of nanostructures into MCF7 cell lines. Further, the photothermal studies accomplished at IC₅₀ concentration for 6 h of treatment and laser exposure for 15 min reported that aptamer-conjugated nanobipyramids were more effective and specific toward MCF7 cell lines than aptamer-conjugated nanostars. <b>Conclusion:</b> This work establishes a platform for the development of tailored photoablation based gold nanostructures for <i>in vivo</i> studies. The investigation on cytotoxic effects and photothermal efficiency of anisotropic spiked gold nanostructures are requisite. Gold Nanostars (GNS), nanobipyramids (GNB) possess exceptional tip-enhanced plasmonic characteristics. GNB and GNS were synthesized and surface modified with MUC1 aptamer. GNB and GNS exhibited photothermal conversion efficiency of 14.5 and 14.1%, respectively. GNB and GNS are much less cytotoxic after aptamer conjugation. Compared with aptamer-GNS, aptamer-GNB exhibited higher selective cellular internalization toward MCF7 cell lines. Photoablation studies revealed that MCF7 cell lines were more severely damaged by aptamer-GNB than by aptamer-GNS.