Preparation of PEGylated nedaplatin liposomes with sustained release behavior for enhancing the antitumor efficacy of non-small cell lung cancer.

Nedaplatin (NDP) plays an important role in the chemotherapies of non-small cell lung cancer (NSCLC). However, dose-limiting toxicities such as myelosuppression and drug resistance restrict its clinical application. Herein, we intended to overcome these defects by developing a PEGylated liposomal formulation encapsulated NDP (NDP-LPs). For the first time, we found the incompatibility between NDP and natural phospholipids such as egg phosphatidylcholine (EPC) using the high-performance liquid chromatography (HPLC) method. The orthogonal experimental design was applied to optimize the conditions for preparing NDP-LPs, with encapsulation efficiency (EE) as the evaluation indicator. The physicochemical properties of optimized NDP-LPs were further characterized, including particle size, zeta potential, EE, drug release profiles, and so on. Results showed that a significantly sustained-release profile of NDP-LPs was observed and the releasing time of NDP could reach as long as 8 days. At the cellular level, NDP encapsulated in the PEGylated liposomes enhanced its cellular uptake and possessed potent cytotoxic activity. After intravenous injection, NDP-LPs could accumulate at tumor sites and effectivelyinhibit tumor growth of mice without obvious adverse effects. In conclusion, our results demonstrated that PEGylated liposomes could serve as a promising carrier to enhance the therapeutic effects of NDP.