Fabrication Of Mesoporous Silica-based Nano Drug Delivery Systems For Cancer Combination Therapy

At present,cancer incidence and morbidityare rapidly growing world-wide,and cancer is to rank as the leading cause of death.It is main challenge to enhance the anticancer efficiency and lower side effect in clinical treatment.As the booming of novel therapeutic way,the combination of two or more treatments is a promising strategy to improve tumor inhibition and reduce damages to healthy cells.It is vital how to effectively deliver different therapeutic agents to tumor site for combination therapy.Therefore,the fabrication of nano drug delivery systems is potential candidate.In this thesis,mesoporous silica with excellent biocompatibility was chosen to fabricate nanodrug delivery systems for combination therapy.The main content of this thesis are as follows:1.Taking advantage of the photothermal property of the reduced graphene oxide(rGO),rGO/MSN/C18 PEG delivery system had been constructedvia supramolecular interactionbetween polymeric reduced graphene oxide and mesoporous silica nanoparticles.And then,therapeutic drug doxorubicin had been loaded in rGO/MSN/C18 PEG to obtain nanomedicines rGO/MSN/C18PEG@DOX.All obtained date indicated that rGO/MSN/C18PEG@DOXwith uniform nano-size exhibited excellent stability and great photo-thermal effects.Compared with the single chemotherapyor photothermal therapy,rGO/MSN/C18PEG@DOX showed enhanced tumor inhibitionfor photothermal-chemotherapy.2.Because AuNPs have surface plasmon resonance,under light irradiation the plasmonical excitation of AuNPs can produce reactive oxygen species(ROS)for photodynamic therapy.Herein,we fabricated reductive responsive nanodrug delivery system MSN-Au-PEG@DOX through growing spherical gold nanoparticles(AuNPs)on the surface of mesoporous silica nanoparticles by in-situ reduction method.MSN-Au-PEG@DOXhad uniform particle size,good stability and biocompatibility.Intumor,the higher glutathione concentrationenvironment could lead to release DOX.Moreover,under light irradiation at 550 nm AuNPscould produce ROSunder irradiation and induce apoptosis of tumor cell,combining chemotherapy and photodynamic therapy,MSN-Au-PEG@DOX showed enhanced anticancer efficacy.