Construction Of Imprinted Biosensor Based On Biomass Carbon And Metal Nanocomposites And Its Performance Research

Immobilized bioactive substances as recognition elements are the key parts of biosensors,however,bioactive substances are often affected by high temperature,acidity and alkalinity environment,which easily leads to the decrease of sensitivity and stability of biosensors.Molecularly imprinted polymers(MIPs)as recognition elements can simulate the specific recognition process of antigen and antibody.Compared with bioactive substances,MIPs have better stability and cheapness.In addition,development and application of MIPs also promote the diversity of recognition elements in biosensors and make biosensors more practical.In summary,two kinds of molecularly imprinted biosensors were constructed for the detection of uric acid and dipyridamole in urine and human serum.Through a series of characterization and electrochemical performance tests,the following results were obtained:1.Biomass carbon enwrapped Ni nanoparticles(Ni@BC)were prepared by one-step solid-state calcinations of the withered leaves of firmiana platanifolia and Ni(NO3)2·6H2O,and MIPs were prepared by electrochemical polymerization on the surface of Ni@BC.Ni@BC and MIPs have been proved to be successfully preparedthrougha series of characterization methods,then it is applied to the electrochemical detection of uric acid.The results showed that the linear range of uric acid detection was 0.01-30 ?mol/L and detection limit was 0.008 ?mol/L,the recovery of uric acid in human urine was 91.26% to 113.39%.2.Gold nanoparticles enwrapped ferric oxide(Fe3O4@Au)were successfully by hydrothermal method and sodium citrate reduction method,which was mixed with multi-walled carbon nanotubes(MWCNT-NH2)to prepare MWCNT-Fe3O4@Au.Microspheric MIPs with uniform size were prepared by precipitation polymerization.MWCNT-Fe3O4@Au and MIPs have been proved to be successfully preparedthrougha series of characterization methods.Then it is applied to the electrochemical detection of dipyridamole.The results showed that the linear range of dipyridamole detection was 0.5-1900 ng/m L and the detection limit was 0.03 ng/m L.The recovery rates of dipyridamole base on standard addition method in healthy human serum was 95.0%-103.6%.