Objective To prepare cisplatin cubic liquid crystal nanoparticles (Cis-LCNP), determine the prescription ratio and process conditions through orthogonal experiments, and investigate the in vitro drug release and cytotoxicity characteristics of Cis-LCNP.

Methods The Cis-LCNP was prepared by injection method. Taking the encapsulation rate as the index, a 4-factor 3-level orthogonal design experiment was adopted to screen the optimal prescription process. The morphology and particle size of nanoparticles were investigated using a polarizing microscope and particle size analyzer. The cytotoxicity of cisplatin and Cis-LCNP on MCF-7 cells was detected using CCK-8 toxicity.

Results The optimal prescription of Cis-LCNP was 900 mg of glycerol monooleate, 100 mg of poloxamide 407, 90 mg of cisplatin and 30 mL of deionized water. The average encapsulation rate of Cis-LCNP was 72.6%, and the cumulative release rate in vitro within 24 hours was 79.8%. The CCK-8 experiment showed that within a certain concentration range, compared with cisplatin, the cytotoxicity of cisplatin cubic liquid crystal nanoparticles was significantly higher, and they had stronger cytotoxic drug characteristics.

Conclusions The Cis-LCNP prepared by injection method is simple in preparation, stable in process, and has good sustained-release characteristics and cytotoxic effects.