Liquid chromatographic determination of isoniazid, pyrazinamide and rifampicin from pharmaceutical preparations and blood

Development of recycled and miniaturized electroanalytical sensor: Probing isoniazid determination in environmental water matrices

Surface water pollution has become relevant because growing population and intense industrial activities. Thus, to protect the environment from contamination, recently the electroanalytical sensors that require small sample volume and easy preparation have shown a prominent performance for pharmaceuticals monitoring. For this purpose, a miniaturized electrochemical platform was developed based on recycling obsolete computer integrated circuits (microchips), fitting with the ideals of green chemistry and circular economy. The gold microelectrodes array (Au-μEA) was easily exposed by polishing the device surface and then characterized by optical microscopy, scanning electron microscopy and cyclic voltammetry. To enhance the analytical performance for isoniazid detection, the Au-μEA was modified with electrochemically reduced graphene oxide (ERGO). The developed sensor presented a linear range between 5 and 100 μmol L-1 and a limit of detection of 1.38 μmol L-1 demonstrating a reliable performance. Looking to its environmental application, the ERGO/Au-μEA sensor was used for isoniazid quantification in lagoon, river, tap water and synthetic effluent spiked samples with recovery values between 92.5 and 108.4%. Thus, this research field opens up new possibilities in global water-related issues contributing with innovative sustainable solutions.

Novel Electrochemical Sensor for Rifampicin based on Ionic Liquid Functionalised TiO2 Nanoparticles

Aim::

The main strategy of this study is to develop a novel ionic liquid functionalised metal nanocomposite based electrochemical sensor with potential applications for the sensitive electrochemical detection of rifampicin.

Background::

Tuberculosis (TB) is a widespread disease that is caused by the gram-positive Mycobacterium tuberculosis (MTB). In addition, for several decades TB has become a constant threat to human health, however due to the accessibility of broad-spectrum antibiotics (rifampicin, pyrazinamide, isoniazid, and ethambutol), which are active against the bacterium, the social and economic burden for sufferers from the illness remains to be huge. Specially, in countries, like India and sub Saharan Africa, it is one of the common diseases affecting members from all age groups. So, this work is aimed at developing a novel electrochemical sensor for the determination of rifampicin (RIF) in pharmaceutical samples.

Objective::

To synthesis and characterization of the novel liquid functionalised metal nanocomposite. Fabrication of glassy carbon electrode with potent electrode modifiers whose applicability as electro catalysis agents towards rifampicin is investigated.

Method::

In this work, a nanocomposite based on trihexyltetradecylphosphonium-bis-(2,4,4-trimethylpentyl)-phosphinate ([P14, 6, 6, 6] [(C8H17)2 PO2)]) ionic liquid functionalised titanium oxide nanoparticles (TiO2NPs) and multiwalled carbon nanotubes (MWCNTs) were used in the modification of a highly sensitive electrochemical sensor for quantification of rifampicin in pharmaceutical formulations. The modified glassy carbon electrode (GCE) were characterised by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD).

Results::

The electrochemical behaviour of RIF was studied on the modified electrode by the cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. At pH 6.0 in phosphate buffer solution (PBS), the anodic peak current value of RIF obtained with the fabricated electrode is 7 times greater than with the bare GCE electrode. The anodic peak current value and concentration of RIF showed a good linear relationship in the range of 0.015–2.8 μM, with the limit of detection (LOD) of 0.0218 μM and limit of quantification (LOQ) 0.3120 μM respectively.

Conclusion::

Under the optimal conditions, the IL-f-TiO2NPs-MWCNTs-GCE provided a relatively lower detection limit and wider linear range compared to other previous procedures. The proposed electrochemical sensor had potent catalytic activity for RIF oxidation and provided important quantitatively reproducible analytical performance. Finally, this modified electrode was successfully applied to the determination of RIF in real pharmaceutical samples.

Simultaneous determination of three antituberculosis drugs in the serum of patients with spinal tuberculosis by capillary electrophoresis

The pharmacokinetic variations of a single drug in an antituberculosis regimen are associated with acquired drug resistance and therapy failure. This study aimed to develop a simple and effective method for monitoring the serum levels of isoniazid (INH), rifampicin (RFP), and pyrazinamide (PZA), three antibiotics used in patients with spinal tuberculosis using capillary electrophoresis (CE). A standard solution of INH, RFP, and PZA was prepared and mixed with serum to prepare the standard curve. The detection limit, quantification limit, precision, stability, repeatability, and sample recovery were determined. Then, INH, RFP, and PZA were measured from the leftover serum samples of all patients with spinal tuberculosis who were treated with 2SHRZ/2.5H2R2Z2 combined with surgery in a tertiary hospital in Qinghai from October 2015 to September 2017. A total of 107 patients with spinal tuberculosis treated using the 2SHRZ/2.5H2R2Z2 regimen combined with surgery were included in this study. All three antibiotics had linear standard curves with high correlation coefficients (R² = 0.9997, 0.9994, and 0.9986). The recovery rates were 98.1% for INH, 96.5% for PZA, and 97.2% for RFP. The results from the serum samples showed that the plasma concentrations of INH (4.989 ± 1.692 μg mL^-1) and RFP (9.400 ± 1.711 μg mL^-1) reached effective therapeutic concentrations in all patients, but not PZA (33.860 ± 1.830 μg mL^-1). The CE method for measuring INH, RFP, and PZA simultaneously in serum samples of patients with spinal tuberculosis is simple, rapid, and sensitive. This method is suitable for the routine monitoring of INH, RFP, and PZA concentrations in the serum of patients with spinal tuberculosis.

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.

Bimetallic cobalt-iron diselenide nanorod modified glassy carbon electrode: an electrochemical sensing platform for the selective detection of isoniazid

The increasing demand of a sensitive and portable electrochemical sensing platform in pharmaceutical analysis has developed widespread interest in preparing electrode materials possessing remarkable properties for the electrochemical determination of target drug analytes. Herein, we report the synthesis, characterization and application of bimetallic cobalt-iron diselenide (FeCoSe₂) nanorods as electrode modifiers for the selective detection of a commonly used anti-tuberculosis drug Isoniazid (INZ). We prepared FeCoSe₂ nanorods by a simple hydrothermal route and characterized these by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and temperature-programmed reduction (TPR) techniques. The electrochemical characterization of FeCoSe₂ modified GCE was performed by cyclic voltammetry (CV) and square wave anodic stripping voltammetry (SWASV). Under optimized experimental conditions, a linear current-concentration response was obtained for INZ in the range of 0.03–1.0 μM, with very low limit of detection 1.24 × 10⁻¹⁰ M. The real applicability of the designed FeCoSe₂/GCE sensing platform was adjudicated by the detection of INZ in biological samples.

FeCoSe₂ bimetallic nanorods were synthesized by hydrothermal method. The modified electrode responded excellently towards isoniazid detection with LOD of 1.24 × 10⁻¹⁰ M. FeCoSe₂/GCE showed applicability for INZ detection in real samples.

Simultaneous detection of ethambutol and pyrazinamide with IL@CoFe2O4NPs@MWCNTs fabricated glassy carbon electrode

For the first time, we report a novel electrochemical sensor for the simultaneous detection of ethambutol (ETB) and pyrazinamide (PZM) using 1-ethyl-3-methylimidazolium tetrafluoroborate ([Emim][BF₄]) ionic liquid (IL) assimilated with multiwalled carbon nanotubes (MWCNTs) decorated cobalt ferrite nanoparticles (CoFe₂O₄NPs) on the surface of glassy carbon electrode (GCE). The surface morphological and electrochemical properties of the IL@CoFe₂O₄NPs@MWCNTs was characterized with X-ray diffraction (XRD), transmission electron microscope (TEM), thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FTIR) and cyclic voltammetry (CV), differential pulse voltammetry (DPV) respectively. Moreover, the obtained results of CV demonstrated that the 9-folds enhancement in the electrochemical signals was achieved with IL@CoFe₂O₄NPs@MWCNTs@GCE compared to that of a bare GCE. Additionally, the simultaneous electrochemical detection of ETB and PZM was successfully accomplished using IL@CoFe₂O₄NPs@MWCNTs over a wide-range of concentration with good limit of detection (3S/m) of 0.0201 and 0.010 μM respectively. The findings of this study identify IL@CoFe₂O₄NPs@MWCNTs@GCE has promising abilities of simultaneous detection of ETB and PZM in pharmaceutical formulations.

An innovative green sensing strategy based on Cu-doped Tragacanth/Chitosan nano carbon dots for Isoniazid detection

Although Isoniazid (INH) is one of the drugs used as the first line treatment of tuberculosis, its high concentrations in the human body can cause severe complications such as; recurrent seizures, profound metabolic acidosis, coma and even death. Hence it is necessary to designing the sensors capable of detecting very low amounts of drug. A Cu doped Tragacanth/Chitosan carbon dot (CD) with excellent optical properties and photo-thermal stability was synthesized, characterized and used for sensing Isoniazid by a fluorescence Off-ON mechanism based on redox reaction between INH and Fe³⁺ as quencher. During the first step of reaction, Fe³⁺ bind to the CDs and due to an electron transfer process the fluorescence intensity of CDs is quenched. There after by introduction of Isoniazid to the CDs-Fe³⁺ system, Fe³⁺ converts to Fe²⁺ and the fluorescence was recovered. Experiments confirm that new method has high ability to detect low concentration of Isoniazid even in the presence of other drugs and interfering materials. In conclusion, this innovative strategy for developing a low cost and sensitive sensor can be used in future health-related programs.

Effect of Mobile Phase pH on the Electrospray Ionization Efficiency and Qualitative Analysis of Pharmaceuticals in ESI + LC-MS/MS

The effect of mobile phase pH on positive ionization process and retention time of nine pharmaceuticals on ultra-performance liquid chromatography-electrospray-tandem mass spectrometry (LC-MS/MS) was discussed. The effective use of high and low mobile phase pH in LC-MS/MS qualitative analyses method was also evaluated by comparing the instrument detection limit, quantification limit, precision, linearity and signal to noise (S/N) under low and high mobile phase pH. In this work, six mobile phase pH that ranged between pH 2 and pH 10 were used to evaluate the effect of the mobile phase pH changes on the ionization process in electrospray ionization. Results revealed that high mobile phase pH ionized more pharmaceuticals molecules and gave a higher signal than low mobile phase pH in positive ionization mode. The results proved that ammonium ion was better as a proton donor in high pH mobile phase than the hydronium ion in acidic mobile phase. The results revealed that the qualitative LC-MS/MS analyses method by using high mobile phase pH has better performance for most analytes in terms of sensitivity, precision, linearity and S/N than the low mobile phase pH.

A chitosan grafted mesoporous carbon aerogel for ultra-sensitive voltammetric determination of isoniazid

A screen-printed carbon electrode (SPCE) was modified with chitosan (Chit) supported on carbon aerogel (CA) to obtain an electrochemical sensor for the tuberculosis drug isoniazid (INZ). The interconnected mesoporous structure of Chit/CA provides a large surface area (S_BET = 461 m² g^-1) and good porosity (V_Tot = 0.69 cm³ g^-1). Besides, the modified SPCE displayed enhanced electrocatalytic activity due to the presence of numerous active sites (such as >C=O, -NH-, -NH₂, -OH). Figures of merit include (a) a typical working voltage of 0.28 V (vs. Ag/AgCl), (b) high sensitivity (8.09 μA μM^-1 cm^-2), (c) a wide linear response to INZ (0.01-115 μM) and (d) a low detection limit (8 nM). The modified electrode has successfully been applied to the determination of INZ in spiked serum and urine, and recoveries ranged from 97.8 to 99.8%. Graphical abstract Schematic illustration of preparation and applications of a nanocomposite consisting of chitosan (Chit; CS) supported on carbon aerogel (CA) for electrochemical detection of isoniazid.

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.

Fabrication of a SnO2–graphene nanocomposite based electrode for sensitive monitoring of an anti-tuberculosis agent in human fluids

For electrochemical oxidation of INH on a SnO₂–Gr/GC electrode the voltammetric signal was observed at various electrolyte pH values.

Isoniazid: A Review of Characteristics, Properties and Analytical Methods

Isoniazid is a synthetic antimicrobial and one of the most important first-line drugs used in the treatment of tuberculosis. Since it was introduced in the therapy in 1952, the drug remains at the front line of the antituberculosis treatment mainly due to its potency and high selectivity against Mycobacterium tuberculosis. Pharmaceutical analysis and therapeutic drug monitoring of isoniazid in both, pharmaceuticals and biological samples, plays an important role to comprehend aspects regarding to bioavailability, bioequivalence and therapeutic monitoring during patients following-up. In the last case, validated and simple methods are extremely useful for Public Healthy in order to guarantee the drug efficacy, safety and reduce the tuberculosis resistance. Among the available analytical tools, HPLC-based methods coupled to ultraviolet or mass spectroscopy are the most widely used techniques to quantify isoniazid. Therefore, this review highlights the main analytical methods reported in the literature for determination of isoniazid focusing in HPLC-based methods.

Bioanalysis of antitubercular drugs using liquid chromatography

Tuberculosis is a life threatening disease and second to HIV in terms of deaths due to infectious diseases. Drug resistance development of the first-line drugs is a major concern in the treatment of this disease. There is no comprehensive and critical review in the literature of the bioanalytical methods for the determination of anti-tubercular agents from last two decades. This work offers a detailed account on the liquid chromatographic methods reported in the literature for the estimation of various anti-tubercular drugs. Major emphasis is given to sample preparation process, sensitivity of method, chromatographic separation conditions and detection systems used in their bioanalysis.

Validation of a simple HPLC-UV method for rifampicin determination in plasma: Application to the study of rifampicin arteriovenous concentration gradient

In clinical practice, rifampicin exposure is estimated from its concentration in venous blood samples. In this study, we hypothesized that differences in rifampicin concentration may exist between arterial and venous plasma. An HPLC-UV method for determining rifampicin concentration in plasma using rifapentine as an internal standard was validated. The method, which requires a simple protein precipitation procedure as sample preparation, was performed to compare venous and arterial plasma kinetics after a single therapeutic dose of rifampicin (8.6 mg/kg i.v, infused over 30 min) in baboons (n=3). The method was linear from 0.1 to 40 μg mL(-1) and all validation parameters fulfilled the international requirements. In baboons, rifampicin concentration in arterial plasma was higher than in venous plasma. Arterial Cmax was 2.1±0.2 fold higher than venous Cmax. The area under the curve (AUC) from 0 to 120 min was ∼80% higher in arterial plasma, indicating a significant arteriovenous concentration gradient in early rifampicin pharmacokinetics. Arterial and venous plasma concentrations obtained 6h after rifampicin injection were not different. An important arteriovenous equilibration delay for rifampicin pharmacokinetics is reported. Determination in venous plasma concentrations may considerably underestimate rifampicin exposure to organs during the distribution phase.

Quantification of rifampicin in human plasma and cerebrospinal fluid by a highly sensitive and rapid liquid chromatographic-tandem mass spectrometric method

A highly sensitive and rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed to measure the levels of the antitubercular drug rifampicin (RIF) in human plasma and cerebrospinal fluid (CSF). The analyte and internal standard (IS) were isolated from plasma and CSF by a simple organic solvent based precipitation of proteins followed by centrifugation. Detection was carried out by electrospray positive ionization mass spectrometry in the multiple-reaction monitoring (MRM) mode. The assay was linear in the concentration range 25-6400 ng/mL with intra- and inter-day precision of <7% and <8%, respectively. The validated method was applied to the study of RIF pharmacokinetics in human CSF and plasma over 25 h period after a 10 mg/kg oral dose.

A new hybrid double divisor ratio spectra method for the analysis of ternary mixtures

A new spectrophotometric method was developed for the simultaneous determination of ternary mixtures, without prior separation steps. This method is based on convolution of the double divisor ratio spectra, obtained by dividing the absorption spectrum of the ternary mixture by a standard spectrum of two of the three compounds in the mixture, using combined trigonometric Fourier functions. The magnitude of the Fourier function coefficients, at either maximum or minimum points, is related to the concentration of each drug in the mixture. The mathematical explanation of the procedure is illustrated. The method was applied for the assay of a model mixture consisting of isoniazid (ISN), rifampicin (RIF) and pyrazinamide (PYZ) in synthetic mixtures, commercial tablets and human urine samples. The developed method was compared with the double divisor ratio spectra derivative method (DDRD) and derivative ratio spectra-zero-crossing method (DRSZ). Linearity, validation, accuracy, precision, limits of detection, limits of quantitation, and other aspects of analytical validation are included in the text.

Design of an optical sensor for indirect determination of isoniazid

The characterization of an optical sensor membrane is described for indirect determination of isoniazid. The sensing membrane was consisted of immobilized 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT) on a triacetylcellulose membrane. The procedure is based on the reaction of Fe(III) with isoniazid in the presence of PDT. Fe(III) is reduced by isoniazid to Fe(II) which forms a complex with PDT. The complex shows an absorption maximum at 558nm. By measuring the absorbance of the complex at this wavelength, isoniazid can be determined in the range of 0.62-6.15microgmL(-1). This method was applied to the determination of isoniazid in pharmaceutical formulation and enabled the determination of isoniazid in microgram quantities.