Eco-friendly HPTLC method for simultaneous analysis of sofosbuvir and ledipasvir in biological and pharmaceutical samples: Stability indicating study

Trio-Colored Appraisal of Microwave-Assisted Synthesis of Carbon Quantum Dots as a Fluorescence Turn Off Nanoprobe for Analyzing Ledipasvir in Tablets and Rat Feces: Study of Silymarin Impact on Excretion Recovery

The current work offers a rigorous way for the microwave-assisted synthesis of N and S doped carbon quantum dots (QDs). The latter are deemed highly sensitive and selective fluorescence sensors that were widely investigated in pharmaceutical analysis. Quenching of luminescence of the prepared QDs in lab fabricated sensor at λ emission = 418 nm after excitation at 370 nm was implemented to quantify the anti-HCV drug Ledipasvir (LDP). LDP showed a linear response within the dynamic range of 1-40 μM. The calculated LDP detection and quantification limits were 313.06 and 948.67 nM, respectively. Besides the analysis of LDP in bulk and commercial dosage form, the scope of application extended to evaluate the effect of the nutraceutical silymarin (liver support) on the excretion of LDP in rat feces. The compliance with the green and white analytical chemistry fundamentals is comprehensively investigated and compared with selected versatile reported procedures. Numerous prevalent metrics, namely, analytical eco-scale, AGREE, RGB12, RGB fast, BAGI, and complex GAPI, were employed. Our developed fluorometric procedure demonstrated great sensitivity, selectivity, and functionality that outperformed other sophisticated platforms. Thus, the utility of the depicted procedure in pharmaceutical analysis and studying pharmacokinetics aspects is profoundly proven.

Sofosbuvir: A comprehensive profile

Sofosbuvir, a nucleotide analogue, is an antiviral medication that belongs to the class of direct-acting antivirals (DAAs). It is primarily used in the treatment of chronic hepatitis C virus (HCV) infections. Sofosbuvir works by inhibiting the replication of HCV, disrupting its ability to produce RNA and effectively reducing the viral load in the body. This chapter offers a comprehensive examination of sofosbuvir, including its nomenclature, physiochemical attributes, synthesis, and thermal analysis. Furthermore, it presents various analytical methods employed for both spectrophotometric and chromatographic assessments of sofosbuvir in different matrices.

Robust high-performance thin-layer chromatography (HPTLC) method for stability assessment and simultaneous quantification of epigallocatechin-3-gallate and rosmarinic acid in lipid-based nanoparticles and biological matrices

INTRODUCTION

Skin cancer poses a significant health risk globally, necessitating effective and safe therapeutic interventions. Epigallocatechin-3-gallate (EGCG) from green tea and rosmarinic acid (RA) from herbs like rosemary offer promising anticancer properties. Combining these compounds may enhance their effectiveness, prompting the need for a reliable analytical method to quantify them.

OBJECTIVE

Herein, we present the development and validation of a high-performance thin-layer chromatography (HPTLC) method for concurrent quantification of EGCG and RA in lipid-based nanoparticles and biological samples.

METHODOLOGY

The method underwent optimisation through design of experiments (DoE), resulting in the establishment of robust chromatographic conditions. The separation process utilised aluminium HPTLC plates coated with silica gel 60 F254 as the stationary phase, with the mobile phase comprising ethyl acetate, toluene, formic acid, and methanol in a ratio of 4:4:1:1 v/v.

RESULTS

The retention factor (Rf) values obtained were 0.38 for EGCG and 0.61 for RA. The method demonstrated linearity over a range of 100-500 ng/band for both compounds with excellent correlation coefficients. Limits of detection and quantification were determined, indicating high sensitivity. Precision evaluations revealed relative standard deviation below 2%, ensuring method reproducibility. Recovery assays in lipid-based nanoparticles, plasma, and urine samples demonstrated excellent recoveries (96.2%-102.1%). Forced degradation studies revealed minimal degradation under various stress conditions, with photolytic degradation showing the least impact.

CONCLUSION

The developed HPTLC method offers a rapid, sensitive, and reliable approach for quantifying EGCG and RA, laying the groundwork for their further investigation as anticancer agents alone and in combination therapies.

Green "turn-off" luminescent nanosensors for the sensitive determination of desperately fluorescent antibacterial antiviral agent and its metabolite in various matrices

Nitazoxanide (NTX) is an antimicrobial drug that was used for the treatment of various protozoa. However, during the coronavirus pandemic, NTX has been redirected for the treatment of such virus that primarily infect the respiratory tract system. NTX is now used as a broad-spectrum antiviral agent. In this study, a highly sensitive and green spectrofluorometric method was developed to detect NTX in various dosage forms and its metabolite, tizoxanide (TX), in human plasma samples using nitrogen and sulfur co-doped carbon quantum dots nanosensors (C-dots). A simple and eco-friendly hydrothermal method was used to synthetize water soluble C-dots from citric acid and l-cysteine. After excitation at 345 nm, the luminescence intensity was measured at 416 nm. Quenching of C-dots luminescence occurred upon the addition of NTX and was proportional to NTX concentration. Assessment of the quenching mechanism was performed to prove that inner filter effect is the underlying molecular mechanism of NTX quenching accomplished. After optimizing all experimental parameters, the analytical procedure was evaluated and validated using the ICH guidelines. The method linearity, detection and quantification limits of NTX were 15 × 10-3-15.00 µg/mL, 56.00 × 10-4 and 15 × 10-3 µg/mL, respectively. The proposed method was applied for the determination of NTX in its commercial pharmaceutical products; Nanazoxid® oral suspension and tablets. The obtained % recovery, relative standard deviation and % relative error were satisfactory. Comparison with other reported spectrofluorimetric methods revealed the superior sensitivity of the proposed method. Such high sensitivity permitted the selective determination of TX, the main metabolite of NTX, in human plasma samples making this study the first spectrofluorimetric method in literature that determine TX in human plasma samples. Moreover, the method greenness was assessed using both Eco-Scale and AGREE approaches to prove the superiority of the proposed method greenness over other previously published spectrofluorimetric methods for the analysis of NTX and its metabolite, TX, in various dosage forms and in human plasma samples.

Analytical approaches for determination of COVID-19 candidate drugs in human biological matrices

Since the outbreak of the COVID-19 pandemic, the use of antiviral and other available drugs has been considered to combat or reduce the clinical symptoms of patients. In this regard, it would be necessary to choose sensitive and selective analytical techniques for pharmacokinetic and pharmacodynamic studies, monitoring of drug concentration in biological fluids, and determination of the most appropriate dose to achieve the desired effect on the disease. In the present study, the analytical techniques based on spectroscopy and chromatography with different detectors for diagnosis and determination of candidate drugs in the treatment of COVID-19 in human biological fluids are reviewed during the period 2015-2022. Moreover, various sample preparation and extraction techniques, are being used for this purpose, such as protein precipitation (PP), solid-phase extraction (SPE), liquid-liquid extraction (LLE), and QuEChERS (quick, easy, cheap, effective, rugged, and safe) are investigated.

Simple simultaneous determination of moxifloxacin and metronidazole in complex biological matrices

A simple, sensitive and rapid RP-HPLC method is presented, for the first time, for the simultaneous determination of moxifloxacin hydrochloride and metronidazole in different biological fluids including saliva and plasma without any matrix interference. The separation was performed using ACN and phosphate buffer (30 : 70% v/v) as the mobile phase on a Zorbax Eclipse Plus-C18 column attached to a guard column. The method was validated according to the FDA guidelines for bioanalytical method validation and was successfully applied for simultaneous determination of the studied drugs in saliva and plasma samples. The good precision and selectivity of the developed method allow it to be used for routine therapeutic drug monitoring of such drugs and it presents a simple and sensitive analytical tool for performing versatile pharmacokinetics and bioavailability studies. A DAD detector is valuable to determine each drug at its maximum wavelength to ensure high sensitivity. Determination of such a combination in saliva introduces a quick and non-invasive alternative to blood analysis.

Exploring an experimental combination of analytical quality by design and green analytical chemistry approaches for development of HPTLC densitometric protocol for the analysis of barnidipine hydrochloride

An experimental combination of analytical quality by design and green analytical chemistry approaches is introduced to develop an high-performance thin-layer chromatography (HPTLC) approach to quantify barnidipine hydrochloride in the pharmaceutical matrix. The analytical quality by design approach was introduced to green analytical chemistry to enhance protocol knowledge while ensuring efficiency and reducing environmental impacts, energy consumption and analyst visibility. This analytical approach was systematically addressed by exploring failure mode effect analysis, risk assessment and optimization design. Subsequently, a screening of primary variables was performed to select the aptest proportion of solvents in the mobile phase resulting from the principles of green analytical chemistry. Failure mode effect analysis and a risk assessment study were attempted to estimate the critical method parameters (CMPs). The influence of the CMPs on critical analytical attributes, i.e. retention factor and peak area, was assessed through a screening design. A response surface methodology was then executed for the critical analytical attributes as a concern of the determined CMPs, and the conditions for excellent resolution were determined using a desirability procedure. The established protocol was validated in compliance with the International Conference on Harmonization guideline Q2(R1) and showed excellent specificity and sensitivity.

Recent advances in the chromatographic determination of the most commonly used anti-hepatitis C drug sofosbuvir and its co-administered drugs in human plasma

Sofosbuvir is a direct-acting antiviral drug that inhibits hepatitis C virus (HCV) NS5B polymerase, which in turn affects the virus replication inside biological systems. The clinical importance of sofosbuvir is based not only on its effect on HCV but also on other lethal viruses such as Zika and severe acute respiratory syndrome coronavirus disease 2019 (SARS-COVID-19). Accordingly, there is a continuous shedding of light on the development and validation of accurate and fast analytical methods for the determination of sofosbuvir in different environments. This work critically reviews the recent advances in chromatographic methods for the analysis of sofosbuvir and/or its metabolites in pure samples, pharmaceutical dosage forms, and in the presence of other co-administered drugs to highlight the current status and future perspectives to enhance its determination in different matrixes.

A Review on Analytical Strategies for the Assessment of Recently Approved Direct Acting Antiviral Drugs

Human beings are in dire need of developing an efficient treatment against fierce viruses like hepatitis C virus (HCV) and Coronavirus (COVID-19). These viruses have already caused the death of over two million people all over the world. Therefore, over the last years, many direct-acting antiviral drugs (DAADs) were developed targeting nonstructural proteins of these two viruses. Among these DAADs, several drugs were found more effective and safer than the others as sofosbuvir, ledipasvir, grazoprevir, glecaprevir, voxilaprevir, velpatasvir, elbasvir, pibrentasvir and remdesivir. The last one is indicated for COVID-19, while the rest are indicated for HCV treatment. Due to the valuable impact of these DAADs, larger number of analytical methods were required to meet the needs of the clinical studies. Therefore, this review will highlight the current approaches, published in the period between 2017 to present, dealing with the determination of these drugs in two different matrices: pharmaceuticals and biological fluids with the challenges of analyzing these drugs either alone, with other drugs, in presence of interferences (pharmaceutical excipients or endogenous plasma components) or in presence of matrix impurities, degradation products and metabolites. These approaches include spectroscopic, chromatographic, capillary electrophoretic, voltametric and nuclear magnetic resonance methods that have been reported during this period. Moreover, the analytical instrumentation and methods used in determination of these DAADs will be illustrated in tabulated forms.

Analytical Methods for Determination of Antiviral Drugs in Different Matrices: Recent Advances and Trends

Viruses are the main pathogenic substances that cause severe diseases in humans and other living things. They are among the most common microorganisms, and consequently, antiviral drugs have emerged to prevent and treat viral infections. Antiviral drugs are an essential drug group considering their prescription and consumption rates for different diseases and indications. Therefore, it is crucial to develop accurate and precise analytical methods to detect antiviral drugs in various matrices. Chromatographic techniques are used frequently for the quantification purpose since they allow simultaneous determination of antivirals. Electrochemical methods have also gained importance since the analysis can be performed quickly without the need for pretreatment. Spectrophotometric and spectrofluorimetric methods are used because they are simple, inexpensive, and less time-consuming methods. The purpose of this review is to present an overview of the analysis of currently used antiviral drugs from 2010 to 2021. Since studies on antiviral drugs are numerous, selected publications were reviewed in this article. The analysis of antiviral drugs was divided into three main groups: chromatographic, spectrometric, and electrochemical methods which were applied to different matrices, including pharmaceutical, biological, and environmental samples.