Synthesis And Electrochemical Sensor Of Imprinted Polymer Materials Based On Boronic Acid Group

In this paper,molecularly imprinted gel-polymers,with white or light yellow,were synthesized by the thermal polymerization in squeous solution of acrylamide?1.0 M?,3-acrylamidophenylboronic acid?AABA,0-0.1 M?,N,N-methylenebisacrylamide?0.1-0.3 M?and ammonium persulphate?0.2 M?.The reaction condition is stirring for 11 hours under nitrogen protection at 0?,and MIPs transforms phase at 50 degrees.Glucose was removed by soaking,and the glucose imprinted polymer?Glu-MIPs?is obtained.Glu-MIPs is elastic,and the elasticity decreases with the addition of N,N-methylenebisacrylamide.After drying,Glu-MIPs is transparent and solid,and the color deeps with the increase of AABA concentration.The Glu-MIPs is characterized by infrared spectroscopy,alizarin red?ARS?color experiment,water content and swelling ratio.By infrared spectrum test,the stretching vibration of Glu-MIPs in 1450cm^-1,1523 cm^-1,1660 cm^-1is C=C of benzene,and 707 cm^-1,798 cm^-1,is disubstituted benzene absorption.Vibration absorption at 1410 cm^-1and 1110cm^-1 is B-O and B-C.Vibration absorption are significantly strengthened with the increase of AABA concentration.It can be concluded that AABA can be linked to polyacrylamide gel-network structure through polymerization reaction to form a network structure with boric acid group.This network structure ba-sed on the addition of glucose as template molecule,between the structure of the hydroxyl groups can form multiple boric acid ester,prepared with hole ar emutually complementary with the glucose molecule structure.In Glu-MIPs color experiments in 0.5000 g/L of ARS solution for 12h,imprinted samples show the"yellow-white-yellow"three layer structure.With a description of this special structure block ARS combined with boronic acid group.Glu-MIPs water exists in the form of free water and bound water,the effect of crosslinking agent on water content was greater than that of AABA.If both are doubled,the former percentage drops about 2%and 8%of latter.The swelling ratio of Glu-MIPs at 20?-50?was less than 0.5.Comparison of AABA and crosslinking agent is doubled,the swelling rate decreased less than 0.1,while the latter is reduced in about 3.On the basis of Glu-MIPs,the platinum electrode?S=1cm²?was modifi-ed via in situ polymerization method.According to the conditions of simple operation,short elution time and strong adhesion on the platinum surface.Electrochemical test mainly use B_0.1 samples modified platinum.Cyclic voltammetry test,Glu-MIPs test electrode identification and accum-ulation of glucose in 0.02M?p H=7.4 PBS?glucose solution,compared with no MIT treatment of Glu-MIPs modified electrode,the peak current after trea tment increased from 3.99×10^-4A to 7.48×10^-4 A,enhance the rate of 87.5%.In 0.02 M glucose,mannitol,and maltose?p H=7.4 PBS?solution,the oxidation peak was compared with the Glu-MIPs modified electrode without MIT treatm-ent.And the peak value is maltose>mannitol>glucose.After dispose of MIT,the peak value changed to glucose>mannitol>maltose.It is can beex-plain that structure of the imprinted unit can select imprinted molecules.When the concentration of 0.2 m M¹.6 m M was measured in glucose?pH=7.4 PBS?,the difference of the voltammetric response was linear?R²=0.9906?.The test of stability,with the increase of the number of elution,the oxid-ation peak is reduced,after fifth times the peak tends to balance.