Synthesis And Application Of Nano-silica Spheres Based On BODIPY-based Hypochlorite Fluorescent Probe And PH And Light Dual-control Drug Delivery

This paper is focused on two parts: A highly sensitive and selective hypochlorite fluorescent probe based on oxidation of hydrazine via free radical mechanism;AND logic-like pH-and light-dual controlled drug delivery by surface modified mesoporous silica nanoparticles.a.Part one.Developing fluorescent probes for selective and sensitive detection of hypochlorite has received much attention,because hypochlorite is closely related to human health.In this work,a new fluorescent probe based on dipyrromethene boron difluoride(BODIPY)fluorophore using hydrazine as detecting group for hypochlorite was synthesized and fully characterized.The reaction of the probe with sodium hypochlorite is complete within 1 min in phosphate-buffered saline,and the fluorescence of the system significantly enhanced.The probe also exhibits admirable sensitivity and selectivity as well.The results of nuclear magnetic resonance monitoring and high-performance liquid chromatography analysis indicate that the detection process plausibly involves a free radical oxidation mechanism.b.Part two.Recently,the controlled drug delivery system has become a potential platform for biomedical application.Herein,we developed a pH and light-dual controlled cargo release system exhibiting AND logic based on MCM-41 mesoporous silica nanoparticles,which was surface modified using ?-cyclodextrin(?-CD)with imine bond and azobenzene derivative.The complex of ?-CD and azobenzene derivative effectively blocked the cargo delivery in pH = 7.0 phosphate buffered saline(PBS)solution without 365 nm UV light irradiation.The cargo was fully released when both factors of acidic environment(pH = 5.0 PBS)and 365 nm UV light irradiation were satisfied,meanwhile only very little cargo was delivered if one factor was satisfied.The result also demonstrates that the opening/closing of the gate and the release of the cargo in small portions can be controlled.If each channel of the material is treated as a house,?-cyclodextrin is seen as a door on the house and the pH control part and the light control part are seen as two locks on the door,then you can open the door only if you have two keys.After door opening,goods in the house can move out.In order to precisely controlling the release of the cargo from the material and to reduce the side effects of the drug on normal tissue before reaching the lesion,we design and prepared this dual-controlled drug delivery system.