Biogenic gold nano-triangles: cargos for anticancer drug delivery.

We present synthesis of biogenic gold nano triangles (GNTs) using Azadirachta indica leaf extract at inherent pH (5.89) and its application in efficient drug delivery of doxorubicin (DOX) (anticancer drug). The main idea was to take advantage of large surface area of GNTs which has 3 dimensions and use the plant peptides coated on these triangles as natural linkers for the attachment of DOX. Sucrose density gradient centrifugation (SDGC) and dialysis methods were used for separation of the GNT from mixture of GNPs. Flocculation parameter (FP) was used to check stability of GNT which was found to be exceptionally high (0-0.75) due to the biological capping agents. DOX attachment to GNT was verified using Fourier transformed infra-red (FTIR) spectroscopy. The complex thus formed was found to be less toxic to normal cells (MDCK cells) and significantly toxic for the cancerous cells (HeLa cells). Drug loading efficiency was found to be 99.81% and DOX release followed first order release kinetics. Percentage drug release was found to be more than 4.5% in both acidic (5.8) as well as physiological pH (7.2) which is suitable for tumor targeting.