Anionic long‐circulating liposomes for delivery of radioiodinated antisense oligonucleotides

Abstract

AbstractLong‐circulating liposomes have been widely used to enhance efficacy of gene therapy. Antisense therapy might increase the efficacy of radiation or chemotherapy; therefore, we undertook to optimize the composition of the liposomal delivery vehicles. The radiolabeling efficiency, radiochemistry purity, and specific radioactivity of radioiodinated antisense oligonucleotides (ASON) were 71.66 ± 7.73, 98.33 ± 0.39%, 4.09 ± 0.11 MBq/nmol. Radioiodinated ASON remained stable in 0.01 M HEPES buffer and human serum even after incubation for 4 hours. Mean diameter of the anionic long‐circulating liposomes (ALCL) was 504 ± 31.76 nm with a polydispersity index (PDI) of 0.107 ± 0.008 before extrusion, 115 ± 8.5 nm with a PDI of 0.103 ± 0.002 after extrusion. The zeta potential of ALCL was −29.23 ± 0.45 mV. ALCL prepared for this study provided 70.28 ± 1.84% encapsulation efficiency. Compared with other liposome formulations, the ALCL mediated enhanced cellular uptake (32.51 ± 1.44%) by MCF‐7 breast cancer cells (p<0.05).Practical applications: Drug delivery systems can in principle provide enhanced efficacy and/or reduced toxicity for anticancer agents. LCL have become a commonly used carrier for gene therapy recently. ALCL are promising for the mediated radiation and antisense therapy for breast cancer which is the leading cause for women.