The Electrochemical Study Of Psychotropic Drugs On Quantitative Detection And Effects To Dopamine

Dopamine(DA)is an important catecholamine neurotransmitter,and DA abnormal secretion is one of the important factors causing mental illness.Olanzapine and lithium carbonate are the main drugs for the treatment of chronic schizophrenia and bipolar disorder,but the pharmacological effects have not been confirmed.Moreover,olanzapine and lithium carbonate have significant side effects and low blood concentration thresholds.Therefore,studying the effects of olanzapine and lithium carbonate on dopamine,as well as qualitative and quantitative detection of dopamine,olanzapine and lithium carbonate,has important biomedical significance.Electrochemical technology can qualitatively and quantitatively analysis the electrochemical redox properties of substances,and effectively achieve precise detection of drug concentration because of fast response speed,high sensitivity,and simple operation.This paper firstly investigates these two aspects using highly conductive modified materials:1.A disposable sensing electrode based on carbon paper was designed for electrochemical detection of dopamine and psychotropic drugs.The physical characterization of carbon paper was carried out using infrared spectroscopy and scanning electron microscopy.The electrode kinetics of DA,olanzapine and lithium carbonate were studied by voltammetry,and the electrochemical oxidation mechanism was analyzed.Secondly,effect of drug concentration on the electrochemical response of DA was studied.Finally,the detection limit of carbon paper electrodes for drugs was evaluated.The experimental results show that carbon paper with high electron transfer ability significantly improves the detection peak current.Different chemical properties of drugs have different effects on DA oxidation.The olanzapine fouling on the electrode surface due to the irreversible adsorption,which make sensing activity weakenand thus reduce the DA oxidation peak current.However,the fixed DA oxidation peak potential at 220 mV indicates no interaction between olanzapine and DA.The hydrolysis effect of lithium carbonate increases the solution pH from 7.47 to9.73,leading to DA oxidation peak potential negatively shift from 216 mV to 60 mV,and accompanied by a 94% decrease in peak current,indicating that lithium carbonate had an effect on dopamine oxidation.In addition,the detection limits of the carbon paper electrode for olanzapine and lithium carbonate are 0.189 μM and 0.356 mM,respectively,which are lower than the corresponding drug concentration thresholds,indicating that the designed sensor has good sensing and detection performance.2.Gold nanoparticles/carbon black/chitosan(AuNPs/CB/CS)modified electrode was prepared by one-step electrodeposition.The AuNPs/CB/CS modified materials were characterized by SEM,XRD and electrochemical impedance detection.Here studied the electrode kinetics of DA and drugs,as well as effect of drug concentration on the electrochemical response of DA.The detection limit of drugs on AuNPs/CB/CS modified electrodes was evaluated using chronoamperometry.The experimental results show that the high electron transfer ability of gold nanoparticles and the high conductivity of carbon black enhance the current catalytic ability of the modified electrode.The effect of the addition of olanzapine and lithium carbonate on the electrochemical response of DA is similar to the detection results of carbon paper electrodes,indicating that within the scope of this study,the drug’s effect on DA is common and not interfered by modified materials.In addition,the detection limits of AuNPs/CB/CS modified electrodes for olanzapine and lithium carbonate are 0.315μM and 0.432 mM,respectively,which are lower than the corresponding drug concentration thresholds,indicating that the sensor has certain application prospects.