Anodic voltammetry of fluphenazine at different solid electrodes

Electrochemical Analysis of Antipsychotics

Introduction:

Schizophrenia is seizures accompanied by severe psychotic symptoms, and a steady state of continuation in the form of periods of stagnation. Antipsychotics are now the basis of treatment for schizophrenia and there is no other molecule that is antipsychotic priority in treatment. Antipsychotics can be classified into two groups; dopamine receptor antagonists such as promazine, fluphenazine etc. and serotonin-dopamine antagonists including risperidone, olanzapine, ziprasidone, aripiprazole etc.

Materials and Methods:

Electrochemical methods have been used for the determination of antipsychotic agent just as used in the determination of many drug agents. Nearly all of the antipsychotics are electroactive and can be analyzed by electrochemical methods. Electroanalytical methods offer generally high sensitivity, are compatible with modern techniques, have low cost, low requirements, and compact design. Among the most commonly used types, there are cyclic voltammetry, differential pulse voltammetry, square wave voltammetry and linear sweep voltammetry.

Conclusion:

The aim of this review is to evaluate the main line and the advantages and uses of electroanalytical methods that employed for the determination of antipsychotic medication agents used in schizophrenia. Moreover, applications of the methods to pharmaceutical analysis of Antipsychotics upto- date is also summarized in a table.

From mercury to nanosensors: Past, present and the future perspective of electrochemistry in pharmaceutical and biomedical analysis

Polarography was the first developed automated method of voltage-controlled electrolysis with dropping mercury electrode (DME). Then, hanging mercury drop and static mercury drop electrodes were added as an alternative indicator electrode. In this way, polarography turned formally into voltammetry with mercury electrodes in the electroreduction way. Solid electrodes such as noble metal and carbon based electrodes can be used for the investigation of the compounds for both oxidation and reduction directions, which is called voltammetry. The voltammetric and polarographic techniques are more sensitive, reproducible, and easily used electroanalytical methods that can be alternative to more frequently used separation and spectrometric methods. Furthermore, in some cases there is a relationship between voltammetry and pharmaceutical samples, and the knowledge of the mechanism of their electrode reactions can give a useful clue in elucidation of the mechanism of their interaction with living cells. The voltammetric and polarographic analysis of drugs in pharmaceutical preparations are by far the most common use of electrochemistry for analytical pharmaceutical problems. Recent trends and challenges in the electrochemical methods for the detection of DNA hybridization and pathogens are available. Low cost, small sample requirement and possibility of miniaturization justifies their increasing development.

Electrocatalysis of NADH oxidation using electrochemically activated fluphenazine on carbon nanotube electrode

Electrocatalytic determination of NADH using a hybrid surface-modified electrode with multi-wall carbon nanotubes (MWCNTs) and a novel electrogenerated redox mediator is described. The redox mediator precursor - fluphenazine (Flu) was adsorbed on MWCNT-modified glassy carbon (GC) electrode which was then subjected to electrochemical activation in 0.1 M H2SO4 using cyclic voltammetry (CV) over a range of potentials -0.2 to 1.5 V vs. Ag/AgCl (6 scans at 100 mV s(-1)). Cyclic voltammograms of Flu indicated the formation of a stable electroactive material presenting one reversible redox couple at the formal potential of -0.115 vs. Ag/AgCl in a phosphate buffer (pH7.0) as a supporting electrolyte. The peaks increased linearly with increasing scan rate indicating electroactive molecules anchored to the electrode surface. The GC/MWCNT/Flu electrode efficiently catalyzed the oxidation of NADH with a decrease in the overpotential of about 600 mV and 150 mV compared to the bare GC and GC/MWCNT electrode, respectively. This modified electrode was successfully used as the working electrode in the chronoamperometric analysis. The peak current response to NADH was linear over its concentration range from 15 μM to 84 μM, and correlation coefficient 0.998. The limits of detection (5 μM) and quantitation (15 μM) were evaluated.

Spectroscopic and electrochemical analysis of psychotropic drugs

Psychotropic drugs are an important family of compounds from a medical point of view. Their application in therapy requires methods for the determination in pharmaceutical dosage forms and body fluids. Several methods for their analysis have been reported in the literature. Among the methods, spectrophotometric and electrochemical are very useful for the determination of the drugs. Some of the spectrophotometric methods are based on the formation of the binary and ternary compounds with complexes of metals. The formed compounds are sparingly soluble in water, but quantitatively extracted from aqueous phase into organic solvents and the extracts are intensely colored and stable for a few days. These complexes have been employed in pharmaceutical analysis. The electrochemical procedures are very useful in determination of the psychotropic substances in pharmaceutical preparations.

Second-derivative synchronous fluorescence spectroscopy for the simultaneous determination of fluphenazine hydrochloride and nortriptyline hydrochloride in pharmaceutical preparations

A rapid, simple, and highly sensitive second-derivative synchronous fluorimetric (SDSF) method has been developed for the simultaneous analysis of binary mixtures of fluphenazine hydrochloride (FLZ) and nortriptyline hydrochloride (NTP) in their co-formulated tablets. The method is based upon measurement of the native fluorescence of these drugs at constant wavelength difference (Deltalambda) = 120 nm in acetic acid. The different experimental parameters affecting the fluorescence intensity of the studied drugs were carefully studied and optimized. The fluorescence-concentration plots were rectilinear over the range of 0.25-3.0 and 1-10 microg/ml for FLZ and NTP respectively, with lower detection limits (LOD) of 0.05 and 0.18 microg/ml and quantitation limits of 0.15 and 0.53 microg/ml for FLZ and NTP respectively. The proposed method was successfully applied for the determination of the studied compounds in their synthetic mixtures and in commercial co-formulated tablets. The results obtained were in good agreement with those obtained by the reference methods.