Study On Synthesis And Application Of Hollow Mesoporous Silica Nanoparticles

In the present study,Hollow mesoporous silica nanoparticles?HMSNs?who have the advantages of both the hollow and mesoporous are synthesized as novel adsorbent carriers for catalysis and bio-medicine,especially for sustained release.The inerratic channel structure and spherical hollow part greatly improved its specific surface area,and abundant raw materials,low cost,simple preparation,high bioavailability,easy to chemical modification,and many other advantages also make them a good application prospect.Borneol,as natural ingredients of Chinese medicine,can inhibit bacteria,antipyretic analgesic,promote the drug through the blood-brain barrier,and solve the problem that most of the drugs unable to get into the brain with poor absorption.The borneol are easily loss and expensive,in this topic,we package the borneol into HMSNs to improve the storage stability,and provide a basis for developing new dosage forms of borneol.In this experiment,we also prepare some fluorescent hollow mesoporous silica microspheres with chemical stability and good biocompatibility,which can effectively load drug molecules and use for cell imaging.The Hollow mesoporous silica nanoparticles?HMSNs?prepared by template method have good spherical shape,the diameter is 300 nm.The reaction is carried out in neutral aqueous solution;HMSNs are purified by the composite microspheres with high temperature calcination,their properties are stable,the mechanical strengths are high.We use BET,TEM and FT-IR to characterize them,the hollow part is about 250nm,the thickness of the shell is about 25 nm,the specific surface area is 730.0 m²/g;the pore diameter is 6.58 nm.The study of template removal and sample drying methods show the spray drying-high temperature calcination method are the best one to get ideal HMSNs.In this topic,we use borneol as model drug,menthol as internal standard substance,to study the drug loading capacity of mesoporous silica nanoparticles,and content determination is accomplished by gas chromatography method.The experimental results show that the best coagulant dosage ratio of MCM-41 is 2:1,the best delivery time is 6 h and the drug loading can achieve 40%;and HMSNs can achieve high drug loading with 8:1?coagulant dosage ratio?,and drug loading up to78%within 8 hours,while the volatility of borneol in the system has been greatly improved.This novel drug delivery system provides a new idea for wide application of borneol in the traditional Chinese medicine.Finally,two kinds of hetero atom doping carbon dots?CDs-1,CDs-2?with brilliant fluorescent quantum yield and other fluorescence properties are synthesized by hydrothermal method.The average particle size of CDs-1 is about 6.5 nm;they have high fluorescent efficiency and good stability to the metal ions.CDs-2,with 1nm average size,has good detection sensitivity for Fe³⁺in pure aqueous solution with a broad pH,and strong ant-jamming capability to use for the detection of trace iron.Furthermore,we bond CDs-1 with HMSNs to get composite NPs?CDs-1@HMSNs?;they implement cells dyeing experiments to two different types of lung cancer cells.The results show that the fluorescent materials have stable chemical and optical stability,they can carry on the fluorescent dye imaging without damage to cells,and the fluorescent effect is good.