Experimental Studies Of The Establishment Of Selective Detection Of Epinephrine Or Acetaminophen By Electroanalysis Based On Nanomaterials Modified Electrode

The direction of modern testing technology is the development of the sensing method with rapidness,sensitivity and economy.Meanwhile,electrochemical analytical method had obtained more and more attention due to the characteristics of simple operation,specificity and sensitivity.Correspondingly,the application of electrochemical sensing in pharmaceutical analysis had obtained more and more widely interests.The main technical route of electrochemical sensing is through the application of appropriate and effective modifying electrodes in order to improve the response of selectivity and sensitivity in a particular system.This work focused on the preparation and application of functional nanomaterials for the fabrication of modified electrodes.And then,the specific modified electrodes were employed to the sensing system of metabolism of drug in serum and simultaneous detection of two drug components in compound preparations,respectively.First,Polythionine-Au nanoparticles composites(PTh-AuNPs)prepared from one-step method were applied to fabricate modified electrode for the sensing of epinephrine(EP)in serum;second,graphene quantum dots(GQDs)prepared through fusion were used to fabricate modified electrode for the simultaneous selective detection of acetaminophen(AC)and ascorbic acid(AA)in cold medicines.1: Polythionine-Au nanoparticles composites(PTh-AuNPs)were synthesized through one-step method and then applied to fabricate modified electrode for the selective sensing of epinephrine(EP)This work developed a highly selective electrochemical sensor based on polythionine-Au nanoparticles composites(PTh-AuNPs)modified glassy carbon electrode(GCE)to detect epinephrine(EP).The electrochemical property of the PTh-AuNPs was characterized by electrochemical impedance spectroscop(EIS).Furthermore,the response of the oxidative behavior of EP was obtained on the PTh-AuNPs modified GCE in phosphate buffer saline(pH6.0),which allowed sensitive sensing of EP using the differential pulse voltammetry(DPV)and Cyclic Voltammetry(CV).The electrochemical sensor can selectively measure EP in a wide linear range from 1 to 40 mg/L with a detection limit of 0.3 mg/L(S/N=3)and a high reproducibility in PBS.The developed electrochemical sensor can be favorably applied to detect EP in a diluted serum.Furthermore,good linear regression between the EPconcentrations and the currents in various diluted serum implied the potential of the proposed method as a promising candidate approach for complex clinical conditions.2: Preparation of graphene quantum dots(GQDs)and the application for the detection acetaminophen and vitamin C in cold medicines.Graphene quantum dots(GQDs)is a kind of ideal electrode modified materials with small charge transfer resistance,high electric catalytic activity and large specific surface area.In this present work,GQDs was prepared with citric acid through pyrolysis method and used to fabricate an electrochemical sensor for the simultaneous determination of acetaminophen(AC)and ascorbic acid(AA).The electrochemical property of the GQDs modified glass carbon electrode was characterized by differential pulse voltammetry(DPV)and cyclic voltammetry(CV).The electrochemical response of the modified electrode for AC and AA was investigated and had a good linear relation in the ranges of 5~80 ?mol/L and 25~1350 ?mol/L,respectively.Furthermore,the application of GQDs modified electrodes can measure the concentration range of AC and AA with 1-200 ?mol/L and 25-1400 ?mol/L simultaneously.The detection limit of AC and AA were 0.15 ?mol/L and 10 ?mol/L(S/N=3),respectively.The prepared electrochemical sensor showed high sensitivity,good selectivity and acceptable precision for AC and AA.The experimental results indicated that proposed method can be applied for pharmaceutical analysis about AC and AA in real medicines.