Nano-sized Particles as New Radioisotopes Carriers for Medical Applications

Abstract

Nanotechnology is one of the possible methods to enhance cancer imaging efficacy with minimal side effect using targeted drug delivery technique. Targeted drug delivery system can reduce the side effects of high medicine concentration at selected sites in the body by improving drug effectiveness at lower doses. Gold nanoparticles (GNPs) were synthesized by green synthesis method using both gallic acid (gallic-GNPs) and sodium citrate (citrate-GNPs) with average diameter of 20 nm for both. The produced gallic-GNPs were successfully labeled with technetium-99m with a radiochemical yield of 81.3 % and showed high in-vitro stability in both saline and human serum. The in-vivo biodistribution study of 99mTc-gallic-GNPs in solid tumor bearing mice showed a high accumulation in tumor site with T/NT (target to non-target ratio) of 5.7 after 60 min post injection. The direct intratumoral (I.T) injection of 99mTc-gallic-GNPs showed very high uptake and retention in tumor tissues with a ratio more than 99 %. Citrate-AuNPs were labeled with technetium-99m with a radiochemical yield of 85.2% and showed good in-vitro stability. By studying the biodistribution of 99mTc-citrate-AuNPs in solid tumor bearing Albino mice, a promising data appeared revealed that a high uptake and good retention of 99mTc-citrate-AuNPs in tumor tissues. As a result of these promising results, 99mTc-gallic-GNPs and 99mTc-citrate-AuNPs can be afforded as potential nano-platforms that could be used as promising tumor imaging agents. Key Words: Gold nanoparticles; Gallic acid; Sodium citrate; Tumor; Imaging; Technetium-99m.