Voltammetric assay of rifampicin and isoniazid drugs, separately and combined in bulk, pharmaceutical formulations and human serum at a carbon paste electrode

State of the Art on Developments of (Bio)Sensors and Analytical Methods for Rifamycin Antibiotics Determination

This review summarizes the literature data reported from 2000 up to the present on the development of various electrochemical (voltammetric, amperometric, potentiometric and photoelectrochemical), optical (UV-Vis and IR) and luminescence (chemiluminescence and fluorescence) methods and the corresponding sensors for rifamycin antibiotics analysis. The discussion is focused mainly on the foremost compound of this class of macrocyclic drugs, namely rifampicin (RIF), which is a first-line antituberculosis agent derived from rifampicin SV (RSV). RIF and RSV also have excellent therapeutic action in the treatment of other bacterial infectious diseases. Due to the side-effects (e.g., prevalence of drug-resistant bacteria, hepatotoxicity) of long-term RIF intake, drug monitoring in patients is of real importance in establishing the optimum RIF dose, and therefore, reliable, rapid and simple methods of analysis are required. Based on the studies published on this topic in the last two decades, the sensing principles, some examples of sensors preparation procedures, as well as the performance characteristics (linear range, limits of detection and quantification) of analytical methods for RIF determination, are compared and correlated, critically emphasizing their benefits and limitations. Examples of spectrometric and electrochemical investigations of RIF interaction with biologically important molecules are also presented.

A highly sensitive and ecofriendly assay platform for the simultaneous electrochemical determination of rifampicin and isoniazid in human serum and pharmaceutical formulations

Simple fabrication of an electrochemical sensor for simultaneous determination of rifampicin and isoniazid based on electrochemical modification of SPCE surface with reduced graphene oxide and nickel hydroxide film (Ni(OH)2/rGO/SPCE) without using toxic chemical agents.

Strategic orchestration of MoSe2 microspheres on β-cd functionalized rGO: A sustainable electrocatalyst for detection of rifampicin in real samples

The ill effects of prolonged use of rifamycin antibiotics such as rifampicin accentuates its need for detection in the environment as well as in biological fluids. Antibiotics in water and soil are long-lasting, bio-accumulative, and hazardous to aquatic species as well as human health. To address this issue, a sensing platform has been developed using Molybdenum diselenide (MoSe₂) embedded on reduced graphene oxide (rGO) functionalized with β-cyclodextrin (β-cd) polymer. The formation of hybrid composite was validated with X-ray diffraction analysis (XRD), Raman spectroscopy, fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FE-SEM) with EDX analysis. The formation of microspheres were observed with hexagonal crystal system and P63/mmc space group. Furthermore, the composite was employed to fabricate an efficient electrochemical sensor for detecting the widely used antibiotic, rifampicin (RIF). The results reveal excellent activity of the sensor with a limit of detection (LOD) of 28 nM in a linear working range from 0.019 to 374.5 μM. The sensor also exhibited a high sensitivity of 11.64 μA μM^-1 cm^-2. Additionally, the sensor showed appreciable recovery range when monitored in real-samples such as human serum and urine, and industrial water, and fish samples.

Analytical Methods Practiced to Quantitation of Rifampicin: A Captious Survey

Background:

Rifampicin (RIF), also known as rifampin, a bactericidal antibiotic having broad antibacterial activity against various gram-positive and gram-negative bacteria acts by inhibiting DNA dependent RNA polymerase. RIF has been administered in different dosage forms like tablets, capsules, injections, oral suspension, powder, etc. for the treatment of several types of bacterial infections, including tuberculosis, Mycobacterium avium complex, leprosy and Legionnaires’ disease.

Introduction:

To ensure the quality, efficacy, safety and effectiveness of RIF drug product, effective and reliable analytical methods are of utmost importance. To quantify RIF for quality control or pharmacokinetic purposes, alternative analytical methods have been developed along with the official compendial methods.

Methods:

In this review paper, an extensive literature survey was conducted to gather information on various analytical instrumental methods used so far for RIF.

Results:

These methods were high-performance liquid chromatography (42%), hyphenated techniques (18%), spectroscopy (15%), high-performance thin-layer chromatography or thin-layer chromatography (7%) and miscellaneous (18%).

Conclusion:

All these methods were selective and specific for the RIF analysis.

First Screen-Printed Sensor (Electrochemically Activated Screen-Printed Boron-Doped Diamond Electrode) for Quantitative Determination of Rifampicin by Adsorptive Stripping Voltammetry

In this paper, a screen-printed boron-doped electrode (aSPBDDE) was subjected to electrochemical activation by cyclic voltammetry (CV) in 0.1 M NaOH and the response to rifampicin (RIF) oxidation was used as a testing probe. Changes in surface morphology and electrochemical behaviour of RIF before and after the electrochemical activation of SPBDDE were studied by scanning electron microscopy (SEM), CV and electrochemical impedance spectroscopy (EIS). The increase in number and size of pores in the modifier layer and reduction of charge transfer residence were likely responsible for electrochemical improvement of the analytical signal from RIF at the SPBDDE. Quantitative analysis of RIF by using differential pulse adsorptive stripping voltammetry in 0.1 mol L⁻¹ solution of PBS of pH 3.0 ± 0.1 at the aSPBDDE was carried out. Using optimized conditions (E_acc of −0.45 V, t_acc of 120 s, ΔE_A of 150 mV, ν of 100 mV s⁻¹ and t_m of 5 ms), the RIF peak current increased linearly with the concentration in the four ranges: 0.002–0.02, 0.02–0.2, 0.2–2.0, and 2.0–20.0 nM. The limits of detection and quantification were calculated at 0.22 and 0.73 pM. The aSPBDDE showed satisfactory repeatability, reproducibility, and selectivity towards potential interferences. The applicability of the aSPBDDE for control analysis of RIF was demonstrated using river water samples and certified reference material of bovine urine.

Electroanalysis of isoniazid and rifampicin: Role of nanomaterial electrode modifiers

Thanks to operational simplicity, speediness, possibility of miniaturization and real-time nature, electrochemical sensing is a supreme alternative for non-electrochemical methodologies in drug quantification. This review, highlights different nanotech-based sensory designs for electroanalysis of isoniazid and rifampicin, the most important medicines for patients with tuberculosis. We first, concisely mention analyses with bare electrodes, associated impediments and inspected possible strategies and then critically review the last two decades works with focus on different nano-scaled electrode modifiers. We organized and described the materials engaged in several categories: Surfactants modifiers, polymeric modifiers, metallic nanomaterials, carbon based nano-modifiers (reduced graphene oxide, multi-walled carbon nanotubes, ordered mesoporous carbon) and a large class of multifarious nano composites-based sensors and biosensors. The main drawbacks and superiorities associated with each array as well as the current trend in the areas is attempted to discuss. Summary of 79 employed electrochemical approaches for analysis of isoniazid and rifampicin has also been presented.

Voltammetric Techniques for the Analysis of Drugs using Nanomaterials based Chemically Modified Electrodes

Background:

Electroanalytical techniques play a very important role in the areas of medicinal, clinical as well as pharmaceutical research. Amongst these techniques, the voltammetric methods for the determination of drugs using nanomaterials based chemically modified electrodes (CMEs) have received enormous attention in recent years. This is due to the sensitivity and selectivity they provide on qualitative as well as quantitative aspects of the electroactive analyte under study. The aim of the present review was to discuss the work on nanomaterials based CMEs for the analysis of drugs covering the period from 2000 to present employing various voltammetric techniques for different classes of the drugs.

Methods:

The present review deals with the determination of different classes of drugs including analgesics, anthelmentic, anti-TB, cardiovascular, antipsychotics and anti-allergic, antibiotic and gastrointestinal drugs. Also, a special section is devoted for enantioanalysis of certain chiral drugs using voltammetry. The detailed information of the voltammetric determination for the drugs from each class employing various techniques such as differential pulse voltammetry, cyclic voltammetry, linear sweep voltammetry, square wave voltammetry, stripping voltammetry, etc. are presented in tabular form below the description of each class in the review.

Results:

Various nanomaterials including carbon nanotubes, graphene, carbon nanofibers, quantum dots, metal/metal oxide nanoparticles, polymer based nanocomposites have been used by researchers for the development of CMEs over a period of time. The large surface area to volume ratio, high conductivity, electrocatalytic activity and biocompatibility make them ideal modifiers where they produce synergistic effect which helps in trace level determination of pharmaceutical, biomedical and medicinal compounds. In addition, macrocyclic compounds as chiral selectors have been used for the determination of enantiomeric drugs where one of the isomers captured in the cavities of chiral selector shows stronger binding interaction for one of the enantiomorphs.

Conclusion:

arious kinds of functional nanocomposites have led to the manipulation of peak potential due to drug - nanoparticles interaction at the modified electrode surface. This has facilitated the simultaneous determination of drugs with almost similar peak potentials. Also, it leads to the enhancement in voltammetric response of the analytes. It is expected that such modified electrodes can be easily miniaturized and used as portable, wearable and user friendly devices. This will pave a way for in-vivo onsite real monitoring of single as well as multi component pharmaceutical compounds.

Synergistic design of a tin phosphate-entrapped graphene flake nanocomposite as an efficient catalyst for electrochemical determination of the antituberculosis drug isoniazid in biological samples

A SnP/GRF-modified electrode has potential application in the electrochemical detection of ISZ.

An electrochemical sensor for the simultaneous determination of rifampicin and isoniazid using a C-dots@CuFe2O4 nanocomposite modified carbon paste electrode

In this study, a sensitive carbon paste electrode based on a novel nanocomposite of carbon dots/CuFe₂O₄ (C-dots@CuFe₂O₄) was developed for the simultaneous determination of rifampicin (RIF) and isoniazid (INZ).

Rifampicin determination in human serum and urine based on a disposable carbon paste microelectrode modified with a hollow manganese oxide@mesoporous silica oxide core-shell nanohybrid

This work designed a simple, sensitive, low-cost, and disposable electrochemical platform for the detection of antibiotic rifampicin (RIF) by using a hollow manganese oxide@mesoporous silica oxide (Mn3O4@SiO2) core-shell nanohybrid as sensitive material. The Mn3O4@SiO2 core-shell nanohybrid, prepared by a facile polyacrylic acid soft templating method, was applied to modify a homemade carbon paste microelectrode, which provided a feasible pathway for electron transfer of RIF due to the low density, large surface area, excellent loading capacity, high permeability, and abundant amount of active sites. The electrocatalytic behavior was further used for sensitive detection of RIF by square wave voltammetry. Under optimal conditions, the calibration curve was linear in the range from 30 nmol/L to 3.0 μmol/L. The electrochemical method showed good stability, reproducibility, and selectivity. It could effectively be applied to the determination of RIF in human serum and urine samples.

Recent progress on pyrazole scaffold-based antimycobacterial agents

New and reemerging infectious diseases will continue to pose serious global health threats well into the 21st century and according to the World Health Organization report, these are still the leading cause of death among humans worldwide. Among infectious diseases, tuberculosis claims approximately 2 million deaths per year worldwide. Also, agents that reduce the duration and complexity of the current therapy would have a major impact on the overall cure rate. Due to the development of resistance to conventional antibiotics there is a need for new therapeutic strategies to combat Mycobacterium tuberculosis. Subsequently, there is an urgent need for the development of new drug candidates with newer targets and alternative mechanism of action. In this perspective, pyrazole, one of the most important classes of heterocycles, has been the topic of research for thousands of researchers all over the world because of its wide spectrum of biological activities. To pave the way for future research, there is a need to collect the latest information in this promising area. In the present review, we have collated published reports on the pyrazole core to provide an insight so that its full therapeutic potential can be utilized for the treatment of tuberculosis. In this article, the possible structure-activity relationship of pyrazole analogs for designing better antituberculosis (anti-TB) agents has been discussed and is also helpful for new thoughts in the quest for rational designs of more active and less toxic pyrazole-based anti-TB drugs.

Development and validation of an electroanalytical methodology for determination of isoniazid and rifampicin content in pharmaceutical formulations

Tuberculosis remains a major public health problem, especially in developing countries. Brazil presents the largest number of cases in Latin America and is among the 22 countries considered priorities by the World Health Organization (WHO). The Rio de Janeiro state has the largest number of cases registered in the country. The treatment of patients, commonly, makes use of the drugs isoniazid and rifampicin for six months. This study aimed to develop and validate an electroanalytical methodology, using the technique of differential pulse voltammetry for the determination of these drugs in the associated form, in order to evaluate the quality of medicines distributed in the state of Rio de Janeiro. The potential reduction for the isoniazid and rifampicin were -1.10 and -0.90 V. The developed and validated electroanalytical method presented a linear range of 0.25 to 1.25 mg/L to isoniazid, limits of detection and quantification of 0.05 and 0.14 mg/L, and recovery of 98.2 ± 0.4%; a tracking linear of 0.40 to 2.00 mg/L for rifampicin, with limits of detection and quantification of 0.07 and 0.19 mg/L and recovery of 95.8 ± 0.6%. Six lots of medicines from two pharmaceutical companies were analyzed. Only one of the samples showed unsatisfactory levels of rifampicin.

Electrochemiluminescence from successive electro- and chemo-oxidation of rifampicin and its application to the determination of rifampicin in pharmaceutical preparations and human urine

A novel electrochemiluminescence (ECL) type was proposed based on successive electro- and chemo-oxidation of oxidable analyte, which was different from both annihilation and coreactant ECL types in mechanism. Rifampicin was used as a model compound. No any chemiluminescence (CL) was produced by either electrochemical oxidation or chemical oxidation of rifampicin in KH(2)PO(4)--Na(2)B(4)O(7) (pH 6.6) buffer-dodecyl trimethyl ammonium chloride (DTAC) solution. However, an ECL was observed by electrochemical oxidization of rifampicin in the same solution in the presence of oxidant such as dissolved oxygen, activated oxygen and potassium peroxydisulfate (K(2)S(2)O(8)). The ECL was attributed to electrochemical oxidation of rifampicin to form semiquinone free radical, and then subsequently chemical oxidation of the formed radical by oxidant to form excited state rifampicin quinone. The proposed ECL type introduced additional advantages such as high selectivity, simple and convenient operation, and effective avoidance of side reaction that often took place in homogenous CL reaction, and will open a novel application field. In addition, with the ECL in the presence of K(2)S(2)O(8) as oxidant, a flow injection ECL method for the determination of rifampicin was proposed. The ECL intensity was linear with rifampicin concentration in the range of 1.0 x 10(-7) to 4.0 x 10(-5) mol l(-1) and the limit of detection (s/n=3) was 3.9 x 10(-8) mol l(-1). The proposed method was applied to the determination of rifampicin in pharmaceutical preparations and human urine.

Fast BIA-amperometric determination of isoniazid in tablets

This paper proposes a new, fast and precise method to analyze isoniazid based on the electrochemical oxidation of the analyte at a glassy carbon electrode in 0.1M NaOH. The quantification was performed utilizing amperometry associated with batch injection analysis (BIA) technique. Fast sequential analysis (60 determinations h(-1)) in an unusually wide linear dynamic range (from 2.5 x 10(-8) to 1.0 x 10(-3)M), with high sensitivity and low limits of detection (4.1 x 10(-9)M) and quantification (1.4 x 10(-8)M), was achieved. Such characteristics allied to a good repeatability of the current responses (relative standard deviation of 0.79% for 30 measurements), were explored for the specific determination of isoniazid in isoniazid-rifampin tablet.

Electrochemical oxidation of isoniazid catalyzed by (FcM)TMA at the platinum electrode and its practical analytical application

The electrocatalytic oxidation of isoniazid (INH) by (ferrocenylmethyl)trimethylammonium [(FcM)TMA] at the platinum electrode in 0.10 M Na2SO4 aqueous solution was studied by cyclic voltammetry (CV). Although INH itself showed a very poor electrochemical response at the platinum electrode, the response could be greatly enhanced by using (FcM)TMA as a mediator, which enables a sensitive electrochemical determination of the substrate INH. The reaction rate constant for catalytic oxidation reaction was evaluated as (3.98+/-0.10)x10(3) M(-1) s(-1) by using chronoamperometry (CA). Experimental conditions such as supporting electrolyte and its concentration, solution pH, and the concentrations of the catalyst (FcM)TMA and the substrate INH were investigated to maximize the current efficiency of the electrocatalytic oxidation. The method can be used for the sensitive practical determination of INH, and also opens an avenue for using (FcM)TMA as a mediator in electroanalytical determination which is very simple, cheap, and rapid. Furthermore, no sample pretreatment or time-consuming extraction steps are required prior to the analysis.