Study On PH-responsive Mg-Fe-LDH Capped On Bimodal Mesoporous Silica Nanoparticles As Drug Carrier

In order to improve drug loading capacity,this paper focus on bimodal mesoporous silica(BMMs)that prepared under different kinds of alkaline medium.Compared with traditional mesoporous silca nanoparticles(MSNs)drug carriers,BMMs show show significant advantanges,such as two kinds of mesoporous structure,high surface area,controllable structure.These unique advantages can obviously reduce mass transfer resistance for BMMs loading drug and improve drug loading.These two mesoporous structures can obviously enhance drug loading capacity due to worn-like mesopores of 3 nm and large accumulated holes around 10~30nm.In order to realize the pH-responsive of BMMs,electrostatic interaction between the negative charge of BMMs surface due to its rich Si-OH and the positive charge by stripping Mg-Fe-LDH.Mg-Fe-LDH can dissolve and release the loading FXD under the low pH condition.Therefore,it is important to improve drug loading and cumulative release of LDH@BMMs@FXD.In this study,the BMMs were fabricated by the hydrolysis of TEOS with the cetyltrimethyl ammonium bromide(CTAB)as template by single template method.By changing different alkaline medium that affect the hydrolysis and polycondensation rate,different nano-structures of the BMMs were obtained.The FXD loading capacity of MCM-41 was 7.829mg/100 mg carrier,the AP loading capacity was 20.113mg/100 mg carrier.Compared with MCM-41,the FXD and AP loading capacity of BMMs(alkaline medium is NH3 · H2O)was14.1974mg/100 mg carrier and 43.65mg/100 mg carrier respectively fabricated under the proper condition by orthogonal test(three factors: the amount of CTAB,the amount of H2 O and pH).Also,when the BMMs was fabricated under alkaline medium of Na2HPO4,the FXD loading capacity was 17.850mg/100 mg carrier;and the BMMs was fabricated under alkaline medium of NaOH,the FXD loading capacity was 19.812mg/100 mg carrier.The FXD cumulative release of BMMs was 93.391%and 73.27% respectively under the different alkaline medium.In order to investigate different mass ratio of LDH @BMMs@FXD affect the performance of drug release,the proper mass ratio of BMMs@FXD and LDH is 8:1.Also,pH-sensitivity of LDH@BMMs@FXD is investigated and results indicate that pH 3.0 is a proper buffer condition.