Voltammetric study of acetazolamide and its determination in human serum and urine using carbon paste electrode modified by gold nanoparticle

Recent advances in electroanalytical methods for the therapeutic monitoring of antiepileptic drugs: A comprehensive review

Frequency of seizures is often managed by a wide group of antiepileptic drugs. Regarding the pharmacokinetic variability, narrow targeted range, and difficulty of detecting signs of toxicity based on laboratory responses, therapeutic monitoring of antiepileptic drugs can play a pivotal role in optimizing the drug dosage. Electrochemical sensors and biosensors can facilitate analysis of these drugs due to their unique advantages such as fast analysis, sensitivity, selectivity, and low cost. This review article, for the first time, describes the recent advances in electrochemical sensors and biosensors developed for the analysis of antiepileptic drugs. General electrochemical measuring techniques and types of applied electrode substrates were described first. To simplify the work, various chemical and biological modifiers applied to improve the sensitivity and selectivity of the sensors were classified and explained briefly. Finally, the future prospective on the development of electrochemical platforms in the quantification of antiepileptic drugs will be presented.

Voltammetric Pathways for the Analysis of Ophthalmic Drugs

Background:

This review investigates the ophthalmic drugs that have been studied with voltammetry in the web of science database in the last 10 years.

Introduction:

Ophthalmic drugs are used in the diagnosis, evaluation and treatment of various ophthalmological diseases and conditions. A significant literature has emerged in recent years that investigates determination of these active compounds via electroanalytical methods, particularly voltammetry. Low cost, rapid determination, high availability, efficient sensitivity and simple application make voltammetry one of the most used methods for determining various kinds of drugs including ophthalmic ones.

Methods:

In this particular review, we searched the literature via the web of science database for ophthalmic drugs which are investigated with voltammetric techniques using the keywords of voltammetry, electrochemistry, determination and electroanalytical methods.

Results:

We found 33 types of pharmaceuticals in nearly 140 articles. We grouped them clinically into seven major groups as antibiotics, antivirals, non-steroidal anti-inflammatory drugs, anti-glaucomatous drugs, steroidal drugs, local anesthetics and miscellaneous. Voltammetric techniques, electrodes, optimum pHs, peak potentials, limit of detection values, limit of quantification values, linearity ranges, sample type and interference effects were compared.

Conclusion:

Ophthalmic drugs are widely used in the clinic and it is important to determine trace amounts of these species analytically. Voltammetry is a preferred method for its ease of use, high sensitivity, low cost, and high availability for the determination of ophthalmic drugs as well as many other medical drugs. The low limits of detection values indicate that voltammetry is quite sufficient for determining ophthalmic drugs in many media such as human serum, urine and ophthalmic eye drops.

Efficient Electrochemical Sensor Based on Gold Nanoclusters/Carbon Ionic Liquid Crystal for Sensitive Determination of Neurotransmitters and Anti-Parkinson Drugs

Purpose: Herein we introduce a simple and sensitive sensor for the electrochemical determination of neurotransmitters compounds and anti-Parkinson drugs.

Methods: The electrochemical sensor (Au/CILCE) based on gold nanoclusters modified carbon ionic liquid crystal (ILC) electrode was characterized using scanning electron microscopy and voltammetry measurements.

Results: The effect of ionic liquid type in the carbon paste composite for the electro-catalytic oxidation of L-dopa was evaluated. Highest current response was obtained in case of ILC compared to other studied kinds of ionic liquids. The effective combination of gold nanoclusters and ILC resulted in extra advantages including large surface area and high ionic conductivity of the nanocomposite. L-dopa is considered one of the most important prescribed medicines for treating Parkinson’s disease. Moreover, a binary therapy using L-dopa and carbidopa proved effective and promising as it avoids the short comings of L-dopa mono-therapy for Parkinson’s patients. The Au/CILCE can detect L-dopa in human serum in the linear concentration range of 0.1 μM to 90 μM with detection and quantification limits of 4.5 nM and 15.0 nM, respectively. Also, the Au/CILCE sensor can simultaneously and sensitively detect L-dopa in the presence of carbidopa with low detection limits.

Conclusion: The sensor is advantageous to be applicable for electrochemical sensing of other biologically electroactive species.

Nanomaterials: Electrochemical Properties and Application in Sensors

The unique properties of nanoparticles make them an extremely valuable modifying material, being used in electrochemical sensors. The features of nanoparticles affect the kinetics and thermodynamics of electrode processes of both nanoparticles and redox reactions occurring on their surface. The paper describes theoretical background and experimental studies of these processes. During the transition from macro- to micro- and nanostructures, the analytical characteristics of sensors modify. These features of metal nanoparticles are related to their size and energy effects, which affects the analytical characteristics of developed sensors. Modification of the macroelectrode with nanoparticles and other nanomaterials reduces the detection limit and improves the degree of sensitivity and selectivity of measurements. The use of nanoparticles as transducers, catalytic constituents, parts of electrochemical sensors for antioxidant detection, adsorbents, analyte transporters, and labels in electrochemical immunosensors and signal-generating elements is described.

A highly selective and sensitive Tb3+-acetylacetone photo probe for the assessment of acetazolamide in pharmaceutical and serum samples

A novel, simple, sensitive and selective spectrofluorimetric method was developed for the determination of Acetazolamide in pharmaceutical tablets and serum samples using photo probe Tb³⁺-ACAC. The Acetazolamide can remarkably quench the luminescence intensity of Tb³⁺-ACAC complex in DMSO at pH 6.8 and λ_ex = 350 nm. The quenching of luminescence intensity of Tb³⁺-ACAC complex especially the electrical band at λ_em = 545 nm is used for the assessment of Acetazolamide in the pharmaceutical tablet and serum samples. The dynamic range found for the determination of Acetazolamide concentration is 4.49 × 10^-9-1.28 × 10^-7 mol L^-1, and the limit of detection (LOD) and limit of quantification (LOQ) are (4.0 × 10^-9 and 1.21 × 10^-8) mol L^-1, respectively.

Square wave voltammetric quantification of folic acid, uric acid and ascorbic acid in biological matrix

Nowadays, modified electrodes with metal nanoparticles have appeared as an alternative for the electroanalysis of various compounds. In this study, gold nanoparticles (GNPs) were chosen as interesting metal nanoparticles for modifying of carbon paste electrode (CPE). GNPs and the gold nanoparticles-modified carbon paste electrode (GNPs/CPE) were characterized by UV–Vis spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). GNPs/CPE as a simple and sensitive electrode was used to study three important biological molecules: folic acid (FA), uric acid (UA) and ascorbic acid (AA). Square wave voltammetry (SWV) was used as an accurate technique for quantitative measurements. A good linear relation was observed between anodic peak current (i_pa) and FA (5.2 × 10⁻⁶ – 2.5 × 10⁻⁵ M), UA (1.2 × 10⁻⁶ – 2.1 × 10⁻⁵ M) and AA (1.2 × 10⁻⁶ – 2.5 × 10⁻⁵ M) concentrations in simultaneous determination of these molecules.