Fabrication of Methacrylated-Chitosan based nanolipogel for siRNA delivery

Abstract

In recent year, researches in gene therapy have witnessed several potential therapeutic approaches being developed to battle current diseases. RNA interference (RNAi) has advanced to become a powerful gene silencing strategy in gene therapy due to its highly sequence-specific mechanism at a post-transcriptional level. This strategy has also become increasingly popular due to its wide range of target, cost-effectiveness and minimised side effects. However, RNAi is greatly limited by the gene delivery system currently available. Thus, a highly effective gene delivery system is urgently in need to aid the transportation of the RNA to the target site of action. In the study, we designed and fabricated a crosslinked nanolipogel (NLG) particles using L-α-phosphatidylcholine (EggPC), methacrylated Chitosan (CMA) and SPARC small interfering RNA (siRNA) with the aiming to achieve sustained gene release per dose. Characterisation of the NLG showed that the particles were spherical with the diameter of 139.6 ± 0.76 nm. Subsequently, a 28-day release study was performed which demonstrated that particles have the capability to release siRNA steadily for a prolonged period of time. Furthermore, the residual amount of siRNA in the NLG indicates sustained released profile to exceed 28 days. Quantitative and qualitative uptake studies was carried out to aid in the understanding of NLG particle entry into Human FibroGRO fibroblast cells. After 24 hrs of treatment, 70% cell entry was observed. This study validates the encapsulation efficiency of this gene delivery system as well as the sustained release profile without significantly hindering cell proliferation.