| Antipsychotic drugs are widely used in clinical treatments.In the past years, increasing attentions have been to the treatments of psychiatric disorders,stimulants determination and drugs analysis.Accordingly,antipsychotic drugs relevant to the focus above have attracted enormous interest of researchers.Many analytical methods have been developed to study them.Among these methods,owing to some advantages such as simplicity,sensitivity,rapid response,low-cost,electrochemical methods play an important role in investigating antipsychotic drugs.The object of this thesis is to study the electrochemical behaviors and mechanisms of them and establish more sensitive,simpler and accurate quantitative methods by means of chemically modified electrodes.The new methods are expected to apply in the practical stimulants determination and drugs analysis.In addition,the results obtained are expected to contribute to the improvement in the understanding of the pharmacological action, toxicological action and anabolism schemes of the antipsychotic drugs.Therefore,this thesis is of great theoretical and practical importance.This thesis is divided into six chapters;In chapter 1,we pointed out the importance of this thesis,described briefly the classification of antipsychotic drugs,current research,the advantages and disadvantages of analytical methods established.We suggested studying them by using chemically modified electrodes.Then,the self-assembled monolayers(SAMs) modified electrodes,conducting polymers(CPs)modified electrodes and carbon nanotubes(CNTs)modified electrodes were discussed in detail.Finally,the research scheme of this thesis was proposed.In chapter 2,the electrochemical behavior and mechanism of fluphenazine at dodecanethiol self-assembled monolayer modified gold electrode was investigated.It was found that fluphenazine could effectively accumulate on the modified electrode and generated two anodic peaks at about +0.7 V(vs.SCE)and +0.79 V in 0.05 M Na2B4O7(pH=9.3)buffer solution,respectively.Sensitive and quantitative measurement of fluphenazine based on the former anodic peak was established under optimum conditions.The anodic peak current was linear to fluphenazine concentration in the range from 5×10-7M to 5×10-5M with the detection limit of 5×10-9M.This method was successfully applied to the determination of fluphenazine in drug tablets and proved to be reliable compared with ultraviolet spectrophotometry (UV).In the presence of fluphenazine,the electrochemical oxidation of phenylephrine could be catalyzed.The dodecanethiol self-assembled monolayer was characterized by Fourier transform infrared spectroscopy(FT-IR),surface Raman spectroscopy (Raman),X-ray photoelectron spectroscopy(XPS),electrochemical impedance spectroscopy(EIS),electrochemical probe and contact angle goniometry.In chapter 3.(1)The 16-mercaptohexadecanoic acid self-assembled monolayer modified gold electrode was fabricated and characterized by Fourier transform infrared spectroscopy(FT-IR),surface Raman spectroscopy(Raman),X-ray photoelectron spectroscopy(XPS),electrochemical impedance spectroscopy(EIS), electrochemical probe and contact angle goniometry.(2)The electrochemical behavior and mechanism of clomipramine at the modified electrode was investigated. It was found that clomipramine could effectively accumulate on this electrode and generated a sensitive anodic peak at about +0.86 V(vs.SCE)in 0.05 M Tris-HCl(pH =8.1)buffer solution.Thus,quantitative measurement of clomipramine was established with high sensitivity under optimum conditions.The anodic peak current was linear to clomipramine concentration in the range from 1×10-6M to 5×10-5M with the detection limit of 6×10-9M.This method was successfully applied to the detection of clomipramine in drug tablets and proved to be reliable compared with ultraviolet spectrophotometry(UV).(3)The electrochemical behavior and mechanism of clozapine at the modified electrode was investigated.It was found that clozapine generated a pair of redox peaks at +0.33～+0.4 V(vs.SCE)in 0.05 M Tris-HCl (pH=8.1)buffer solution.Sensitive and quantitative measurement of clozapine based on anodic peak was established under optimum conditions.The anodic peak current was linear to clozapine concentration in the range from 1×10-6M to 5×10-5M with the detection limit of 7×10-9M.This method was successfully applied to the detection of clozapine in drug tablets and proved to be reliable compared with ultraviolet spectrophotometry(UV).In chapter 4,the electrochemical behaviors and mechanisms of phenylephrine and chlorprothixene at poly(4-aminobenzene sulfonic acid)modified glassy carbon electrode were studied.It was found that phenylephrine and chlorprothixene generated an irreversible anodic peak at about +0.89 V(vs.SCE)and +1.04 V in 0.05 M HAc-NaAc(pH=5.0)or NH2CH2COOH-HCl(pH=2.4)buffer solution at the modified electrode,respectively.Sensitive and quantitative measurement for them based on the anodic peaks was established under the optimum conditions.The anodic peak current was linear to phenylephrine and chlorprothixene concentrations from 1×10-7M to 1.5×10-5M and 2×10-6M to 4.5×10-5M,the detection limits obtained were 1×10-8M and 1×10-7M,separately.The modified electrode exhibited some excellent characteristics including easy regeneration,high stability,good reproducibility and selectivity.The method proposed was successfully applied to the determination of phenylephrine and chlorprothixene in drug injections or tablets and proved to be reliable compared with ultraviolet spectrophotometry(UV).The modified electrode was characterized by electrochemical methods.In chapter 5,the electrochemical behaviors and mechanisms of haloperidol and hydroxyzine at multi-walled carbon nanotubes modified glassy electrode were studied. It was found that haloperidol generated a sensitive anodic peak at about +0.86 V(vs. SCE)while hydroxyzine generated a sensitive anodic peak at about +0.83 V and a small anodic peak at about +0.91 V in 0.05 M NaH2PO4-Na2HPO4(pH=7.0)buffer solution.Sensitive and quantitative measurement for them based on the anodic peaks was established under the optimum conditions.The anodic peak current was linear to haloperidol and hydroxyzine concentrations from 1×10-7M to 2.5×10-5M,the detection limits obtained were 8×10-9M and 5×10-9M,respectively.The modified electrode exhibited some excellent characteristics including easy regeneration,high stability,good reproducibility and selectivity.The method proposed was successfully applied to the determination of haloperidol and hydroxyzine in drug tablets and proved to be reliable compared with ultraviolet spectrophotometry(UV).The modified electrode was characterized by electrochemical methods.In chapter 6,we summarized and gave objective comments on the results obtained. Meanwhile,the problems and shortcomings of this thesis were pointed out.Finally, we proposed the objects and schemes of further research.
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