Achiral and chiral separation and analysis of antifungal drugs by HPLC and CE: A comparative study: Mini review

The chromatographic and electrophoretic methods developed for the chiral and achiral analyses if antifungal agents are reviewed. The aim of this review is to compare different methodologies of analytical methods and to explore still the existing analytical problems. Last decade is characterized by dynamic development of instrumental methods that results in advance and diversity of applied analytical procedures. The enantiomeric separation of several compounds, including an antifungal drug and several of its precursors, using high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE) is described in this work. The main focus was given to HPLC, the technique of choice in the analysis of most of the pharmaceutical formulations and biological samples. The columns used were based on polysaccharide derivatives. However, the results show that most of the separations obtained by CE are better, in terms of high resolution and short analysis time. The review discusses the chromatographic analysis of the following triazole antifungal drugs: fluconazole, itraconazole, and terconazole from the first generation and posaconazole, voriconazole, ravuconazole, isavuconazole, and albaconazole from the second generation in their pharmaceutical formulations and biological samples.     

High-Performance Liquid Chromatographic Method for the Simultaneous Determination of Four Flavonols in Food Supplements and Pharmaceutical Formulations

A method using high-performance liquid chromatography with diode array detection (HPLC-DAD) as a powerful separation technique has been developed for the simultaneous determination of the four flavonols rutin, quercetin, kaempferol and isorhamnetin in food supplements and pharmaceutical formulations. The chromatographic separation was achieved in 36?min using a Symmetry C₁₈ column (250?×?3?mm; 5?µm) as the stationary phase and a mixture of methanol, acetonitrile, and pH 2.5 aqueous acetic acid as the mobile phase in gradient elution mode. The analytical wavelengths were 256?nm for rutin, quercetin and isorhamnetin, and 368?nm for kaempferol. An ultrasound-assisted extraction protocol was performed using methanol as solvent. The detection and quantification limits were lower than 0.03?µg mL^?1 and 0.08?µg mL^?1, respectively. The inter-day and intra-day precisions were less than 4.8 and 5.1%, respectively, and the average recoveries were in the range from 96 to 107%. The method was applied for the determination of the studied flavonols in food supplements and pharmaceutical preparations. The satisfactory recovery values demonstrate the potential of the developed method for the determination of the analytes in these samples. In addition, the method is suitable for routine quality control due its ease of operation.     

Simultaneous densitometric analysis of amlodipine,hydrochlorothiazide, lisinopril,and valsartan by HPTLC in pharmaceutical formulations and human plasma

A simple, accurate, and precise high-performance thin layer chromatographic (HPTLC) method has been developed and validated for the simultaneous quantification of antihypertensive drugs, amlodipine (AML), hydrochlorothiazide (HCTZ), lisinopril (LIS), and valsartan (VAL) in their pharmaceutical formulations and human plasma. Separation of the drugs was performed on aluminum-backed layer of silica gel 60?F₂₅₄ using a mixture of methanol–dichloromethane–glacial acetic acid (9.0:1.0:0.1, v/v/v) as the mobile phase. Densitometric determination of the separated spots was done at 215?nm. The retention factors (R_f) obtained under the optimized conditions were 0.56, 0.75, 0.29, and 0.67 for AML, HCTZ, LIS, and VAL, respectively. Linearity of the method was established in the range of 200–1,500?ng/band for AML, 300–1,500?ng/band for HCTZ, 400–2,000?ng/band for LIS, and 1,000–7,000?ng/band for VAL. The limit of detection/limit of quantitation of the method found were 54.21/164.28, 77.27/234.15, 83.45/252.87, and 156.48/474.19?ng/band for AML, HCTZ, LIS, and VAL, respectively. To determine the drugs in spiked plasma samples, solid phase extraction was performed, which provided highly consistent and quantitative recovery for all four drugs. The method was satisfactorily applied for the analysis of different tablet formulations and proved to be specific and accurate for the quality control of these drugs.     

Microemulsion based chromatographic techniques: Past lessons and future directions

Microemulsion Liquid Chromatography (MELC) and Microemulsion Electrokinetic Chromatography (MEEKC) respectively have emerged as new forms of analytical techniques for the separation of drugs of different water solubilities, solving different separation challenges and offer a variety of applications in pharmaceutical industry and routine quality control analysis of drugs. A comprehensive review of the literatures on recent developments in the field of Microemulsion based techniques was made. Various literatures dealing with microemulsion based chromatographic techniques were collected and studied extensively. Major findings of all the important literatures were summarized and classified in an appropriate manner to help reader understand the types, methods and applications of the technique. This article covers basic concepts of microemulsion, their optimization parameters, advantages and disadvantages and a plethora of applications and research done over the last decade. Almost all the major researches done in the field were tried to cover. Microemulsion based chromatographic techniques have been proved to be a newer and interesting technique that is extensively studied nowadays. Due to their polyphasic structure, microemulsion as eluent in both MELC and MEEKC offers a large number of advantages, applications and capability in separating the mixture of components.     

Chiral separation of quinolones by liquid chromatography and capillary electrophoresis

The quinolones are derivatives of oxoquinolines and mostly known for their antibacterial and antiviral activities. Many quinolones are chiral compounds having asymmetric centers and important due to their enantioselective biological activities. In order to study the biological activities of quinolone enantiomers, to control the manufacturing of homochiral drugs and to prepare necessary quantities of pure enantiomers for preclinical or clinical trials, respective chiral separation methods are urgently needed. In this context, the present review discusses chromatographic and electrophoretic methods for the enantioseparation of chiral quinolones and provides some useful information on their physical and pharmaceutical properties. The drawbacks of currently used techniques are revealed and ways to overcome them are outlined. Moreover, recommendations for an optimal choice of a separation protocol are given.     

Sequential injection chromatography against HPLC and CE: Application to separation and quantification of amoxicillin and clavulanic acid

Sequential injection chromatography (SIC) has been recently proposed as an alternative separation technique. SIC has the advantages of inexpensiveness, rapid operation procedure, small dimension, short stabilization time, friendly maintenance process and less reagent consumption. In contrast, SIC has had suffered from some limitations. In the current study, a higher pressure resistant selection valve with additional ports than that available in commercially SIC systems was installed. This development allows achieving solution propulsion without showing leakage and linking more standard/sample solutions. In addition, a new method for the separation and quantification of amoxicillin and clavulanic acid in pharmaceutical formulations has been optimized and validated. A comparative study on the efficiency of the SIC method with previous HPLC and CE methods was conducted as well. Besides the benefits of the instrumentation of SIC, the proposed method has shown some advantages over previous HPLC and CE methods with respect to reagent consumption and sample frequency. Other such analytical characters of the SIC method as resolution, peak symmetry, number of theoretical plates, linearity range, accuracy, precision and limits of detection and quantification, recorded comparable results with those obtained from previous HPLC and CE methods.     

Development and validation of capillary zone electrophoresis and high-performance liquid chromatography methods for the determination of oral anticoagulant edoxaban in pharmaceutical tablets

The incidence of thrombotic complications in SARS-CoV-2 infections has become a global concern; thus, anticoagulants are an integral part of the treatment. Edoxaban (EDX) is an oral anticoagulant suitable for pharmacologic thromboprophylaxis. Herein, two novel analytical methods for EDX determination in tablets are developed and validated using capillary zone electrophoresis (CZE) and high-performance liquid chromatography (HPLC). Operating conditions such as the electrolyte's concentration and pH value, injection time, volume, and the capillary temperature, were optimized. The methods were successfully validated by establishing the linearity, intra- and inter-day precisions (relative standard deviation [%]), accuracy, and robustness. Adequate separation of excipients and degradation products of EDX generated by stress degradation conditions demonstrated the stability-indicating capability of the methods. The analytical procedures were linear in the range of 25–125 µg/ml (r > 0.999), with the limits of detection and quantification of 3.26 and 10.87 µg/ml for CZE and 0.740 and 2.78 µg/ml for HPLC. Although both methodologies are suitable for determining EDX in tablets, CZE provides a greener alternative due to low-cost analysis using less organic solvents and minimizing waste generation.     

Method for trace determination of N-nitrosamines impurities in metronidazole benzoate using high-performance liquid chromatography coupled with atmospheric-pressure chemical ionization tandem mass spectrometry

Genotoxic impurity control has been a great concern in the pharmaceutical industry since the recall of the large round of sartans worldwide in 2018. In these sartans, N-nitrosamines were the main contaminants in active pharmaceutical ingredients and formulations. Numerous analytical methods have been developed to detect N-nitrosamines in food, drugs, and environmental samples. In this study, a sensitive method is developed for the trace determination of N-nitrosamine impurities in metronidazole benzoate pharmaceuticals using high-performance liquid chromatography/atmospheric-pressure chemical ionization tandem mass spectrometry in the multiple reaction monitoring mode. The method was validated regarding system suitability, selectivity, linearity, accuracy, precision, sensitivity, solution stability, and robustness. The method showed good linearity with R² ≥ 0.999 and F_Mandel < F_tab(95%) ranging from 0.33 to 8.00 ng/ml. The low limits of detection of N-nitrosamines were in the range of 0.22–0.80 ng/ml (0.0014–0.0050 ppm). The low limits of quantification were in the range of 0.33–1.20 ng/ml (0.0021–0.0075 ppm), which were lower than the acceptable limits in metronidazole benzoate pharmaceuticals and indicated the high sensitivity of the method. The recoveries of N-nitrosamines ranged from 84% to 97%. Thus, this method exhibits good selectivity, sensitivity, and accuracy. Moreover, it is a simple, convenient, and scientific strategy for detecting N-nitrosamine impurities in pharmaceuticals to support the development of the pharmaceutical industry.     

A Review of Analytical Methods for Codeine Determination

Codeine is derived from morphine, an opioid analgesic, and has weaker analgesic and sedative effects than the parent molecule. This weak opioid is commonly used in combination with other drugs for over-the-counter cough relief medication. Due to the psychoactive properties of opioid drugs, the easily obtained codeine often becomes subject to misuse. Codeine misuse has emerged as a concerning public health issue due to its associated adverse effects such as headache, nausea, vomiting, and hemorrhage. Thus, it is very important to develop reliable analytical techniques to detect codeine for both quality control of pharmaceutical formulations and identifying drug misuse in the community. This review aims to provide critical outlooks on analytical methods applicable to the determination of codeine.     

Simultaneous determination of ten amphetamine designer drugs in human whole blood by capillary electrophoresis with diode array detection

In recent years, a number of new designer drugs have entered the illicit drug market. The methylenedioxyderivatives of amphetamine represent the largest group of designer drugs. This paper describes a method for screening for and simultaneously quantifying 10 2,5-methylenedioxy-derivatives of amphetamine and phenethylamine in human whole blood, using capillary electrophoresis (CE) with diode array detection (DAD). Using an aqueous pH 2.5 phosphate buffer, CE analysis gave peaks with good symmetry and reproducible migration times. Under these experimental conditions, the 10 amphetamines were resolved in 15 min and without interference from biological matrices (blood). Their identification by migration time was confirmed by their UV spectra recorded with a DAD (190-350 nm). The main advantages of the present method lie in its simplicity, clean and reliable extraction from human whole blood and simultaneous detection and quantification by CE-DAD. The applicability of the method was demonstrated by analysis of in vivo rat blood samples. The method was validated according to international guidelines.     

Achiral and chiral analysis of duloxetine by chromatographic and electrophoretic methods,a review on the separation methodologies

Duloxetine (DLX) is a widely used antidepressant drug belonging to the class of selective serotonin and norepinephrine reuptake inhibitors (SNRIs); its efficacy has been demonstrated in the treatment of not only major depressive disorders but also diabetic neuropathic pain, generalized anxiety disorder, fibromyalgia or stress urinary incontinence. It is a chiral substance and is used in therapy in the form of the enantiopure S‐DLX, which is twice as active as R‐DLX. Several methods have been published for the achiral and chiral determination of DLX in pharmaceuticals, biological materials and environmental samples, the majority using liquid chromatography and capillary electrophoresis coupled with different detection techniques (UV detection, fluorescence, mass spectrometry). The aim of the current review is to provide a systematic survey of the analytical techniques used for the determination of DLX from different matrices.     

Development and validation of high-performance liquid chromatography method for determination of clarithromycin in pharmaceutical tablets

Clarithromycin is a very important macrolide antibiotic used to treat bacterial infections in human and veterinary medicine. This study reports the development and validation of cost-effective, simple, precise, accurate, and robust high-performance liquid chromatography (HPLC) for the determination of clarithromycin (CLA) in tablets. Reversed-phase chromatography was conducted using a standard column at 55°C with ultraviolet detection at 215 nm. A mobile phase consisting of acetonitrile –2-methyl-2-propanol –potassium phosphate buffer was used at a flow rate of 1.0 mL/min. The proposed method displayed good linearity, precision, accuracy, robustness, and specificity. The present HPLC was compared with capillary electrophoresis and bioassay methods and the results indicated that there was no significant difference between these methods. Moreover, the obtained results demonstrated the validity of the isocratic HPLC, which allows reliable quantitation of CLA in pharmaceutical samples. Thus, it can be used as a substitute alternative methodology for the routine quality control of this medicine, in situations where other methods are less accessible in the laboratory.     

High-Performance Liquid Chromatography of Domoic Acid,a Marine Neurotoxin,with Application to Shellfish and Plankton

Abstract

A recent outbreak of poisoning resulting from the consumption of cultured blue mussels (Mytilus edulis L.) from a localized area in Eastern Canada has been attributed to the presence of domoic acid (1), a relatively rare neurotoxic amino acid, previously found only in some algae of the family Rhodomelaceae. Studies on aqueous extracts of shellfish tissue indicated that the toxin and several of its isomers could be separated (and isolated in sufficient amounts for subsequent structural identification) by reversed-phase high-performance liquid chromatography (HPLC) with ultraviolet (UV) diode array detection (DAD). Aqueous acetonitrile containing 0.1% v/v trifluoroacetic acid was used as mobile phase. As the retention time and characteristic UV absorption spectrum of 1 (λ_max = 242 nm) permit unequivocal identification, the HPLC-DAD procedure was refined with a microbore column to provide a rapid (5 min), sensitive (0.3 ng detection limit) and reproducible assay method for the determination of 1 in shellfish tissue. Extraction was accomplished by boiling homogenized shellfish tissue for 5 min with distilled water. Extracts were taken through an octadecylsilica solid phase extraction clean-up prior to HPLC. This method has been applied to a variety of shellfish and phytoplankton samples.

BRIEF

Reversed-phase HPLC with ultraviolet diode array detection was used to analyze shellfish tissue and phytoplankton extracts for domoic acid. A rapid (5 min) and sensitive (0.3 ng detection limit) assay is presented.     

HPLC determination of thiol drugs in pharmaceutical formulations using ethacrynic acid as a precolumn ultraviolet derivatization reagent

Summary A high performance liquid chromatographic method has been developed for the determination of aliphatic thiol drugs, such as N-acetyl-L-cysteine, captopril and mercaptopropionylglycine in pharmaceutical formulations. The procedure involves a precolumn derivatization of the thiol drug with ethacrynic acid followed by reversedphase HPLC separation and UV detection. The conditions for a rapid and selective reaction of the thiols with ethacrynic acid have been investigated. The method proved to be suitable for a reliable and selective quality control of commercial dosage forms of the examined thiol drugs.     

Use of Multiplexed CE for Pharmaceutical Analysis

This report describes the evaluation of a multiplexed, 96-capillary array instrument for analytical performance with a view to implementation for routine, high-throughput use. The need for higher throughput analytical capability for today’s busy pharmaceutical laboratory continues to rise. The use of multiplexed capillary electrophoresis is discussed, and the 96 multiplexed capillary array instrument with UV absorbance detection was used to perform high throughput pharmaceutical analysis. Pharmaceutical product assay, pK _a and log P determinations were achieved. Reproducibility of relative migration time and relative peak area between capillaries was found to be acceptable. The multiplexed instrument offered equivalent performance for tablet assay to a conventional CE instrument. Using the multiplexed CE, pK _a values approaching those of the literature values were obtained for a range of drugs. A microemulsion electrokinetic chromatography (MEEKC) method was successfully used without resulting in excessive operating current. The use of multiplexed CE for high throughput analysis has been shown to be a highly viable alternative to HPLC and other conventional analytical techniques.Presented at: CE in the Biotechnology & Pharmaceutical Industries: 7th Symposium on the Practical Applications for the Analysis of Proteins, Nucleotides and Small Molecules, Montreal, Canada, August 12–16, 2005.     

Capillary electrophoresis methods for microRNAs assays: A review

MicroRNAs (miRNAs) are short noncoding RNAs that conduct important roles in many cellular processes such as development, proliferation, differentiation, and apoptosis. In particular, circulating miRNAs have been proposed as biomarkers for cancer, diabetes, cardiovascular disease, and other illnesses. Therefore, determination of miRNA expression levels in various biofluids is important for the investigation of biological processes in health and disease and for discovering their potential as new biomarkers and drug targets. Capillary electrophoresis (CE) is emerging as a useful analytical tool for analyzing miRNA because of its simple sample preparation steps and efficient resolution of a diverse size range of compounds. In particular, CE with laser-induced fluorescence detection is a promising and relatively rapidly developing tool with the potential to provide high sensitivity and specificity in the analysis of miRNAs. This paper covers a short overview of the recent developments and applications of CE systems in miRNA studies in biological and biomedical areas.     

Simultaneous Determination of Atenolol and Chlorthalidone in Pharmaceutical Preparations by Capillary-Zone Electrophoresis

Abstract

A capillary zone electrophoresis (CZE) method for the simultaneous determination of the β-blocker drugs atenolol and chlorthalidone in pharmaceutical formulations has been developed. The CZE separation was performed under the following conditions: capillary temperature, 25°C; applied voltage, 25 kV; 20 mM H₃PO₄–NaOH running buffer (pH 9.0); and detection wavelength, 198 nm. Phenobarbital was used as internal standard. The method was validated and showed not only good precision and accuracy but also good robustness. The method has been successfully applied to the simultaneous determination of both atenolol and chlorthalidone in pharmaceutical tablets.