Fabrication And Characterization Of Polymeric Biomimetic Nanochannels

Ion channels widely exist in cells of living organisms. It is composed of specificprotein and could response to varieties of external stimuli. It plays a crucial role inmetabolism process. According to the biomimics conception, researchers havedeveloped a series of biomimetic smart nanochannels. Benefit from the idealmechanical properties and chemical stabilities, solid nanochannels especially thepolymeric nanochannels are chosed to build all sorts of biosensors, ion rectifyingdevices and energy conversion equipments. Efficient chemical modification promotestheir applications. Detailed descriptions of track-ething and phase seperation blendingmethods are performed. Meanwhile, systematic characterizations and discussions onnanochennels’ modifications are also included. The main works are mentioned asfollowing:(1) Inspired by natural ion channels, asymmetric conical PET singlenanochannels were prepared by track-etching method. Glucose biosensors wereconstructed on the bases of as-prepared nanochannels. Carboxyl groups whichexposed on channel surfaces facilitated the grafting of GOD molecules. Effective porediameters and rectification ratios were reduced by steric hindrance of GOD enzymes.Internal environment was altered due to enzymatic catalytic reactions. Correspondingelectrochemistry signals indicated the detection results. This biosensor behavedextremely low detection limits, ideal repeability and chiral recognition. It isconsidered as a potential novel biosensor in the future.(2) Blending phase seperation is a technology of fabricating polymericmicro-pore membranes. Phase seperation between polymer phase and water pahseoccurred at relatively low temperature. PES porous membranes and modifiedPES/TPQPCl membranes were prepared by blending phase seperation technology.Other than track-etching technology, blending phase seperation technology couldmodify the membrane at the fabrication period. Larger pores and higher porosity wereobtained after mixing hydrophilic TPQP with PES. The modified PES/TPQPCl membranes behave better ion transportation ability at varieties of concentrations, pH,anions and cations.(3) Ag nano-particles can be deposite in conical single PET nanochannel by ionsputtering instrument. Silver layer could reduce pore diameter and increasenanochannel’s rectification ratio. Ag nano particles initiate surface Plasmon resonanceunder visible light. This special quantum effect of Ag nano-particles increased surfacecharge density of the channel and enlarged trans-membrane ionic current. In additon,hydrophilic surface after lighting increased trans-membrane ionic current to someextent. Experiments show that controllable pore size and continuously variable ionrectification metal/polymer composite nanochannels could be prepared by ionsputtering technology.