Bioanalysis of aminoglycosides using high-performance liquid chromatography

Aminoglycosides are broad-spectrum antibiotics used in the treatment of gram-negative bacterial infections. Due to their nephrotoxic and ototoxic potential (narrow therapeutic index), the use of aminoglycoside for clinical indications requires monitoring. The objective of this review was to identify relevant literature reporting liquid chromatographic methods for the bioanalysis of aminoglycosides in both preclinical and clinical settings/experiments. Data on liquid chromatographic methods were collected from articles in an online academic database (PubMed, Science Direct, Scopus, and Google Scholar). All 71 articles published from 1977 to 2020 were included in the review. Reversed-phase liquid chromatography was the most used method for the bioanalysis of aminoglycosides. Fluorescence or ultraviolet detection methods were mostly used from 1977 to 2002 (51 articles), while mass spectrometry was predominantly used as a detector from 2003 to 2020 (15 articles). Sixty-seven articles reported calibration ranges, which varied significantly for the various drugs assayed: some in the range of 0.1-0.5 ng/mL and others 1250-200000 ng/mL. Also, 61 articles reported R2 values (0.964-1.0) for almost all analytes under consideration. Sixty-three articles reported percent recoveries mostly between 61.0 % to 114.0 %, with only two articles reporting recoveries of 4.9 % and 36 %. Out of the 71 reviewed articles, 56 reported intermediate precision values ranging between 0.331 % to 19.76 %, which is within the acceptable limit of 20 %. This review will serve as a guide for research and/or routine clinical monitoring of aminoglycosides in biological matrices.

Ensuring the validity of the results of calibrations and tests by statistical methods

According to the requirements of ISO/IEC 17025:2017, the validity of test and calibration results is ensured, inter alia, by intralaboratory check of the results obtained. In this case, it is preferable to use statistical methods. The ISO 5725 standards define a number of such methods, but the choice of specific methods is left to the laboratory, taking into account the requirements for the adequacy of the effort, resources and time for the purposes of the work performed and the risks of obtaining inappropriate results. In this case, the laboratory itself must in a certain way determine which objects of calibrations (tests) should be predominantly used in checks and what frequency of checks should be foreseen. In connection with the increase in the accuracy and complexity of measuring systems, the need to apply the methods of the theory of random processes becomes more and more obvious. It is shown that the use of the Poincaré plot makes it possible to comprehensively, effectively and visually evaluate changes in the measuring process from the point of view of the dynamics of the obtained measurement results. The results of the check, in particular, the intermediate precision, make it possible to obtain a more realistic evaluation of measurement uncertainty in accordance with ISO 21748. The paper analyses some practical approaches (of varying degrees of complexity) to intralaboratory checks of the validity of calibration (test) results.

The Development and the Validation of a Novel Dissolution Method of Favipiravir Film-Coated Tablets

The aim of this study was to develop and validate a dissolution test for favipiravir release in a tablet dosage form using ultra-high performance liquid chromatography (UHPLC). The dissolution method was developed by testing the solubility of favipiravir in media with different pH values. The results demonstrated that the best dissolution was achieved in phosphate buffer with a pH of 6.8. The amount of favipiravir that was released was about 100% after 30 min. The UHPLC method presented linearity (R = 1.000) in the concentration range of 0.044–0.44 mg/mL. The recovery parameter that was achieved ranged from 102.5% to 104.2%. The system suitability, repeatability, and intermediate precision RSD% results were found to be 0.36%, 1.99%, and 2.49%, respectively. In addition to these parameters and results, an F-test was performed using the Minitab 18 Statistical Software program for the intermediate precision and repeatability results. The standard and sample solutions were found to be stable for 2 days in their respective dissolution medium. This analytical method was also found to be selective for favipiravir. In conclusion, a simple and feasible dissolution method with a short run time of 2.5 min was developed and validated successfully. The obtained results demonstrated that the dissolution test developed here is adequate for its purpose and can be applied as the dissolution method for favipiravir in film-coated tablets for release analyses.

Quantification and Stability Indicating Method Development and Validation of Vismodegib in Bulk and Pharmaceutical Dosage Form by Ultra Performance Liquid Chromatography

Background: Vismodegib (VMD) is a drug of choice for the treatment of basal-cell carcinoma. Present studies carried out to estimate VMD by RP-UPLC technique and to develop a simple, précised, accurate method for routine analysis. Methods: For this purpose Chromatographic conditions used were stationary phase STD BEH C18 column (100 mm x 2.1 mm, 1.8m), a mixture of Methanol:KH2PO4 taken in the ratio 50:50%v/v as a mobile phase with a pH 7.4 and flow rate was maintained at 0.3ml/min, detection wave length was Acquity TUV 254nm, column temperature was set to 30oC and diluent was mobile phase, Conditions were finalized as optimized method. Results: System suitability parameters were studied by injecting the standard six times. Linearity study was carried out between 25% to150% (37.5-225µg/ml) levels, R2 value was found to be as 0.9992. Precision was found to be 0.6 for repeatability and 0.4 for intermediate precision. LOD and LOQ are 0.33 µg/ml and 0.99 µg/ml respectively and results were well under the acceptance criteria. Conclusion: By using above method assay of marketed formulation was carried out and was found 100.12%. Degradation studies of VMD were done, in all conditions purity threshold was more than purity angle and within the acceptable range. The developed method was simple and can be used for routine analysis.

Validated Modernized Assay for Foscarnet in Pharmaceutical Formulations Using Suppressed Ion Chromatography Developed through a Quality by Design Approach

Inspired by the United States Pharmacopoeia (USP) “monograph modernization” initiative, we developed and validated an assay for foscarnet sodium injection solution (“foscavir”), following quality by design (QbD) principles, incorporating design of experiments (DoE) and multivariate data analysis to establish the design space and robust setpoint of the method. The resulting analytical procedure was based on ion chromatography (IC) with suppressed conductivity detection, employing an isocratic carbonate–bicarbonate eluent system. The assay was successfully validated at the robust setpoint conditions, according to the guidelines established by the International Council for Harmonization (ICH). The linear range stretched at least from 5 to 100 mg/L with high repeatability (relative standard deviation, RSD ≤ 0.3%) both at the target concentration (60 mg/L) and at 50% and 150% from this level. Special attention was given to establish a rugged assay that would be easily transferable between laboratories, and the recorded recoveries of 98.2–100.5% for both the formulated drug product and the drug substance during intermediate precision evaluation at different analysis situations indicated that this mission was accomplished. A multivariate assessment of intermediate precision data acquired using an experimental design scheme revealed that the assay was not adversely affected by any of the situation variables, including the use of different liquid chromatography instrument types, regardless of if they were constructed from inert materials or stainless steel that had been passivated, even though such problems have been reported in several previous methods for analysis of foscarnet.

Development and Validation of Head-space Gas Chromatographic Method in Tandem with Flame ionized detection for the determination of Residual solvents in Simeprevir API Synthesis

Residual solvent testing is an integral part of reference material certification. A gas chromatography/flame ionization detector/headspace method has been developed and validated to detect and quantitate commonly used residual solvents in our production processes: Methanol, Tetrahydrofuran, Toluene, Dichloromethane and Dichloroethane in Simeprevir API. A simple and selective HS-GC method is described for the determination & quantification of Residual Solvents in Simeprevir API. Chromatographic separation was achieved on USP G43 equivalent capillary column Thermo Scientific™ Trace GOLD™ TG-624 SilMS, 30m × 0.32mm × 1.8µm column (P/N 26059-3390) using nitrogen as carrier gas by using different temperature gradient of FID Detectors. Linearity was observed in the range 40-120% of standard concentrations for Methanol, Tetrahydrofuran, Toluene, Dichloromethane and Dichloroethane (r2>0.999) for the amount of solvent estimated by the proposed methods was in good agreement. The proposed methods were validated. The accuracy of the methods was assessed by recovery studies at three different levels. Recovery experiments indicated the absence of interference from commonly encountered diluent and API. The method was found to be precise as indicated by the repeatability analysis, showing %RSD less than 10 for Methanol, Tetrahydrofuran, Toluene, Dichloromethane and Dichloroethane. All statistical data proves validity of the methods and can be used for routine analysis of pharmaceutical active ingredients for estimation of Residual Solvents of Methanol, Tetrahydrofuran, Toluene, Dichloromethane and Dichloroethane in Simeprevir. Baseline separation of all five solvents and Simeprevir API is achieved within 20.5 minutes of analysis time. Method validation comprised the following parameters: limit of detection (LOD), limit of quantitation (LOQ), linearity and range, accuracy, precision (repeatability and intermediate precision), system suitability, specificity, and robustness. Linearity and LOQ (ppm) are listed for each solvent in manuscript. The present method was proven to be robust and accurate for quantitative analysis of residual solvent in neat materials.

Method Development and Validation for the Trace Level Quantification of Genotoxic Impurity Oseltamivir Phosphate Related Compound-a in Oseltamivir Phosphate Using LC-MS

A selective and sensitive method has been developed for the determination of ethyl-(3S,4R,5S)-4-acetamido-5-amino-2-azido-3-(pentan-3-yloxy)cyclohexanecarboxylate (OSPRC-A) by using liquid chromatography coupled with mass spectrometer with single mass analyzer (LC-MS).The method was developed by using column DEVELOSIL ODS-UG-5, (50×3.0 mm, 5.0 µm) with linearity range of 0.005% to 0.0151% which meets to quantification level of 150% range. The column oven temperature was maintained at 40ºC. The flow rate was set as 1.5 mL/min. Injection volume was 10 µL and the detection wavelength was 215 nm. The signal to noise ratio values obtained were found to be 4.79 at concentration level of 0.00015% for the limit of detection (LOD) and 13.46 at concentration level of 0.0005% for the limit of quantification (LOQ). The % recovery was found to be in between the range 80.0% to 101.32% at LOQ to 150% level. The result obtained in method precision and intermediate precision are found to be within the specification limit. The percentage RSD for the content of OSPRC-A of method precision was 4.26. The percentage RSD for the content of OSPRC-A for intermediate precision was 4.00. The sample prepared in analytical solution was found to be stable for 24 h. This method can be used for the identification of impurity, OSPRC-A in Oseltamivir phosphate drug substances in its manufacturing.

Development and Validation of Three Potential Genotoxic Impurities by Liquid Chromatography Single Quad Mass Detector in Iomeprol

A liquid chromatography with single quadrupole mass detection method was developed for the determination of potential genotoxic impurities (PGIs) in the Iomeprol active pharmaceutical ingredient. Chromatographic separation was achieved on an Agilent Eclipse plus C8 column (100 mm x 2.1 mm x 1.8 μm) with 0.1% formic acid in water as mobile phase A and acetonitrile as mobile phase B in gradient elution mode at a 0.1 mL/min. Executed validation summary demonstrated that the mass detection method had highly sensitive and selective. A linear calibration curve (correlation coefficient, r> 0.999) was attained at the concentration range of 0.1-125 ppm for three PGI’s. The Limit of Detection of Imp-A, Imp-B and Imp-C in drug substance of Iomeprol is 0.05 ppm. The accuracy was confirmed by calculated recoveries (98.4-101.5%). The precision was tested at three levels: injection repeatability, analysis repeatability and intermediate precision. The calculated relative standard deviations were within the specification. The developed method was able to quantitate all three PGI’s at a concentration level of 1 µg/mL.

Stability Indicating Method Development and Validation of Cenobamate in Bulk and Dosage form by Liquid Chromatography

A simple, Precise, Accurate method was developed for the estimation of Cenobamate by RP-HPLC technique. Chromatographic conditions used are stationary phase symmetry C18 (150 mm* 4.6 mm 5 µm), mobile phase Acetonitrile: 0.01NKH2PO4in the ratio of 55:45 and flow rate was maintained at 1.0ml/min, detection wave length was 272.0 nm; column temperature was set to 30oC. Retention time was found to be 2.908 min. System suitability parameters were studied by injecting the standard six times and results were well under the acceptance criteria. Linearity study was carried out between 25% to150 % levels, R2 value was found to be as 0.999.Precision was found to be 0.5 for repeatability and 0.8 for intermediate precision. LOD and LOQ are 0.01µg/ml and 0.03µg/ml respectively. By using above method assay of marketed formulation was carried out 100.32% was present. Degradation studies of Cenobamate were done, in all conditions purity threshold was more than purity angle and within the acceptable range.