Preliminary study on pH-sensitive lipid bilayer-coated mesoporous silica nanoparticles as a novel drug carrier for antitumor drug

This study plans to prepare lipid bilayer-coated mesoporous silica nanoparticles (LMSNs) which are pH sensitive with core-shell structure to improve the tumor cell lethality of antitumor drug.  The lipid coated mesoporous silica nanoparticles loaded with irinotecan (CPT-11) (CPT-11-LMSNs) were prepared by hot water- film hydration method, and the characterized its morphology, particle size and release in vitro.  Meanwhile, the intracellular uptake and cell toxicity of CPT-11-LMSNs and intracellular accumulation of CPT-11 were evaluated on human breast carcinoma cell line (MCF-7).  The results indicated that the mean diameter of the spherical LMSNs was (120.27 ± 5.91) nm.  The slow release in simulated normal physiological conditions and a rapid release under simulated intracellular condition demonstrated the pH sensitivity of CPT-11-MSNs in vitro.  Moreover, the CPT-11-LMSN could improve the intracellular CPT-11 cumulant 2.1 times and reduce half maximal inhibitory concentration (IC₅₀) values of CPT-11 1.4 times compared with CPT-11-MSNs, demonstrating a stronger cell lethality.