Abstract
Mesoporous silica nanoparticles (MSNs) have some excellent properties, such as high surface areas and large pore volumes, unique mesoporous structure and tunable pore sizes, ease of surface modification, and good biocompatibility. However, nanoparticles (NPs) are introduced to in vivo applications through the bloodstream; they are easily considered as intruders by the innate immune system and cleared by the reticuloendothelial system (RES)/mononuclear phagocyte system (MPS). Therefore, this study utilizesd the approach of erythrocyte membranes (red blood cell membranes, RBCm) coated MSNs camouflage to prolong the circulation lifetime. In the first study project, RBCm coated different sizes of MSNs were investigated. The sizes of MSNs synthesized were 110-450 nm in different concentration of styrene. The properties of MSNs were first analyzed with surface area and porosimetry analyser (ASAP/BET) and thermogravimetric analyzer (TGA). The pore size of MSNs was 12 nm. Then, we confirmed RBCm coated on the surface of MSNs with scanning electron microscopy (SEM), transmission electron microscopy (TEM), zeta potential, and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The thickness of as-prepared RBCm coated MSNs (RBCm@MSNs) were 9-10 nm in different sizes. RBCm@MSNs showed no significant toxicity by cell viability. The accumulative level of RBCm@MSNs in different size were no difference, but amount of big RBCm@MSNs were accumulated 4.5 times more than small one. In vivo experiments, RBCm@MSNs prolonged the blood circulation and accumulated for 4 days. In the second project, MSNs were loaded hydrophobic drug Docetaxel (DTX) and graphene quantum dots (GQD). The loading capacity (LC) and drug encapsulation efficiency (EE) were 72.3 % and 80.3 %, respectively. GQD loaded MSNs were heated to 65 °C in 5 minutes with near-infrared irradiation (808 nm). GQD loaded MSNs combined chemotherapy and thermal therapy to achieve synergistic therapeutic effects. Then, targeting protein drug, Erbitux, modified on the surface of RBCm to enhance treatment effects to A549 (a human lung carcinoma cell line) cancer cells and inhibited the tumor growth after treatments on the third day. This study developed targeting RBCm coated MSNs loaded DTX and GQD produced synergistic therapeutic effect of chemotherapy and thermal therapy to inhibit A549 tumor cells on the mice growth with near-infrared irradiation up to 19 days.