The Detection Of Drug Molecules By Electrochemical Sensors Based On Molecularly Imprinted Polymers

MIT(Molecular Imprinting Technology)has became an important method to artificially synthesize materials which can imitate the specific binding process of biomolecules.MIP(Molecular Imprinted Polymer)sensors are receiving increasing concerns.This thesis focuses on the construction of novel MIP sensors based on the electropolymerization and the inclusion association of functional monomer cyclodextrin,and the MIP film was used as the transducer in the design.The MIP sensors could be applied for the determination of pharmaceuticals.The work mainly includes three parts:(1)The sensor was built on the surface of r-GO modified glassy carbon electrode(GCE).Mitoxantrone(MX)was used as the template while ?-cyclodextrin(?-CD)was used as the monomer to construct a MIP sensor which can be applied to detect MX with high sensitivity and selectivity.SEM was used to characterize the morphology of MIP electrode.CV and DPV were used to characterize the electrochemical properties of MIP electrode.Multiple factors including the formation of electropolymerized film,template extraction,supporting electrolyte and other factors which have influence on the detection of MX were optimized in the experiment.The MIP sensor was used in the quantitative determination of MX.The linear response range was 1 ×1O-5 mol/L to 6×10-8 mol/L with a correlation coefficient of 0.996 and the detection limit was 3 × 10-8 mol/L(S/N=3).The results indicate that the MIP sensor can be employed in the determination of MX with good sensitivity,repeatability and reproducibility.The MIP sensor was successfully applied to the determination of MX in mitoxantrone hydrochloride injection and the result was satisfactory.(2)In this work,?-CD was used as the monomer and to fabricate a Levofloxacin(LVFX)-imprinted MIP sensor on the surface of r-GO modified GCE.The difference of current response between LVFX and isomer of ofloxacin(OFX)was compared by electrochemical experiments.The preparation conditions of imprinted electrode and parameters in determination were optimized.Under the optimized condition,the potential difference between LVFX and OFX on the LVFX-imprinted MIP sensor was 0.020 V,relative difference of current response was 68.3%,and the difference of response time in chronoamperometry experiment was 26 s.The linear range was 1× 10-5 mol/L?8× 10-8 mol/L(R=0.9970)?with the detection limit was 1.47 ×10-8 mol/L(S/N=3).The sensor can be applied to the determination of LVFX tablets and good results are obtained.(3)The sensor was prepared by electropolymerizing y-CD and L-arginine(L-Arg)on the r-GO/GCE while R-propranolol(R-PRO)was used as template molecule.EIS,DPV and other electrochemical methods were utilized to characterize the electrochemical properties of the MIP film and specific recognition ability of MIP electrode for R-PRO.The determination of R-PRO was conducted by using SWV method,and the linear range was 1 × 10-7 mol/L?2× 10-5 mol/L.The detection limit reached 8.9×10-8mol/L(S/N=3).Under the optimized conditions,the poly-y-CD-L-Arg MIP sensor was used to detect PRO in real samples successfully.