Preparation And Study Of Multi-stimulation-responsive Controlled Release Nanocapsules Based On Host-guest Structure Of Supramolecular

In this paper,well-designed rotaxanes are immobilized on the outer surface of mesoporous silica nanoparticles(MSNs)as supramolecular nanometer valve,and the movement of macrocycle molecules along the pseudorotaxane stalk successful achieved the controlled release of cargo molecules.In this paper,a new type of quadruple stimuli-responsive mechanized silica nanoparticles(MSNPs)was constructed.Release of cargo molecules is initiated by acid/Zn2+/base/reduction potentials.Firstly,the pseudorotaxane was synthesized and the working mechanism is studied by the isothermal calorimetry(ITC),one dimensional NMR spectroscopy of host-guest inclusion and mass spectrometry of supernatant after Zn2+ triggering release experiment.The products were characterized by TEM,ED AX,FTIR,XRD,N2 adsorption-desorption isotherms and BET and BJH parameters analysis,thermogravimetric analysis(TGA)characterization,and solid state nuclear magnetic resonance(SS NMR)analysis.The smart nano-containers with acid/Zn2+/alkali/reduction potential-quadruple stimulus response were proven to be successfully preparedFinally,the UV-vis spectra of rhodamineB(RhB),doxorubicin hydrochloride(DOX)and benzotriazole(BTA)and the cargo releasing kinetic curves were obtained using a Shimadzu UV-1800 spectrometer.We conducted cytotoxicity tests and cell uptake tests.It was demonstrated that DOX controlled release under acid stimulation and obvious killing effect on MCF-7 cancer cells.This special release properties make it has broad application Potential in the field of drug delivery in vivo.It was demonstrated that the controlled release of BTA under different acid/base and reduction stimuli was also in line with expectation.This shows high potential for this intelligent nano-container in the field of smart anti-corrosion coating.