Research On Micro-nano Channel Systems For Protein Transport Separation

Proteomics has been an important scientific topic of life activity,however,the protein separation analysis process is time-consuming,then this thesis mainly focuses on improving protein detection and analysis method,aiming at solving the problem of inconvenience,safety of high voltage,adsorption of biological macromolecules of microfluidic chip electrophoresis as well as the problem of multi-functions and low flux of nanofiltration membranes.The main work and conclusions are as follows:1.A simple and effective USB flash disk type microfluidic chip electrophoresis(MCE)was developed by using poly(dimethylsiloxane)(PDMS)based template casting and dry film based PCB etching techniques.The MCE had a microchannel diameter of 375 ?m and effective length of 25 mm.Equipped with a conventional online electrochemical detector,the device enabled rapidly and effectively separation of bovine serum albumin(BSA),lysozyme(Lys)and cytochrome c(Cyt-c)under the low voltage from a computer USB interface.Compared with traditional capillary electrophoresis(CE),the USB flash disk type MCE is not only portable and inexpensive,but also fast with high separation efficiency.2.Microfluidic chip electrophoresis(MCE)is a powerful separation tool for biomacromolecule analysis.However,adsorption of biomacromolecules,particularly proteins onto microfluidic channels severely degrades the separation performance of MCE.Here,an anti-protein-fouling MCE was fabricated using a novel sandwich photolithography of poly(ethylene glycol)(PEG)prepolymers.Photopatterned microchannel with a minimum resolution of 10 ?m was achieved.After equipped with a conventional online electrochemical detector,the device enabled baseline separation of bovine serum albumin(BSA),lysozyme(Lys)and cytochrome c(Cyt-c)under a voltage of 200 V in a short time.Compared with a traditional PDMS MCE made by soft lithography,the PEG MCE made by the sandwich photolithography not only eliminated the need of a master mold and the additional modification process of the microchannel,but also showed excellent antiprotein-fouling properties for protein separation.3.Carbon nanotube(CNT)nanoporous membranes based on pre-aligned CNTs have superior nano-transportation properties in biological science.Herein,we report a smart temperature-and temperature-magnetic-responsive CNT nanoporous membrane(CNM)by grafting thermal-sensitive poly(N-isopropylacrylamide)(PNIPAM)and Fe3O4 nanoparticles(Fe3O4-NPs)on the open ends of pre-aligned CNTs with a diameter around 15 nm via surface-initiated atom transfer radical polymerization(SI-ATRP)method.The inner cavity of the modified CNTs in the membrane is designed to be the only path for ion and protein transportation,and its effective diameter with a variation from ~5.7 nm to ~12.4 nm can be reversible tuned by temperature and magnetic field.The PNIPAM modified CNM(PNIPAM-CNM)and PNIPAM magnetic nanoparticles modified CNM(PNIPAMMAG-CNM)exhibit excellent temperature-or temperature-magnetic-responsive gating property to separate proteins of different sizes.The PNIPAM-CNMs and PNIPAM-MAGCNMs have potential applications in making artificial cells,biosensors,bioseparation and purification filters.