Bioanalytical Method Development and Validation for the Determination of Favipiravir in Spiked Human Plasma by using RP-HPLC

A precise, simple and reproducible reverse phase liquid chromatography (RP-HPLC) method was developed and validated for determination of Favipiravir by using Carbamazepine as internal standard in spiked human plasma. A chromatographic separation was accomplished with Cromasil C18 (250mm x 4.6ID, Particle size: 5 micron) column using mobile phase consists of methanol: water in the ratio (35:65, %v/v), at pH 3.0 with binary gradient system-maintained flow rate at 0.8ml/min. The detection wavelength of drug sample was at 225 nm. Extraction was done by using ethyl acetate as extracting solvent. The retention time of Favipiravir was found to be 6.62 min. The method was found to be linear in the concentration range of 0.2-3.2 µg/ml. Limit of quantitation (LOQ) value was found to be 0.72. The intra- and inter day precision and accuracy lies within the specified range. The recovery studies were found to be in the range of 97.6 to 100.2%. %Relative standard deviation (RSD) was found to be in the range of 0.07-2.80%. All parameters were found to be validated from spiked human plasma. The proposed RP-HPLC method is highly accurate and rapid for the determination of favipiravir in human plasma and can be applied for pharmacokinetic studies and Therapeutic drug monitoring.

Multivariate Model Update Chemometric Methods for Determination of Prednisolone and Esomeprazole in Spiked Human Plasma: a Comparative Study

Background Prednisolone is immunosuppressant and anti-inflammatory drug; it may cause peptic ulcers as a side effect. Esomeprazole is used for treatment of peptic ulcers therefore; the two drugs are co-administered in case of organ transplantation and autoimmune diseases. Objective This work aims to determine simultaneously the two drugs together in bulk and spiked human plasma by eliminating the overlapping between the spectra of each other and the interference of plasma matrix. Methods Two simple and effective model updated chemometric models called principal component analysis (PCA) and partial least square (PLS) were established using UV spectrophotometric data. Results The two updated models have been validated according to the U.S. Food and Drug Administration guidelines with accepted results. The results were statistically compared with those of the reported methods, where no significant difference was found, indicating the validity of the developed methods. The two updated models have been successfully applied for prediction of the proposed drugs with good results regarding accuracy and precision. Conclusion The two updated models are simple, rapid, sensitive, and precise and could be easily applied in quality control laboratories for determination of PRD and ESO, without any preliminary separation steps or interference from plasma matrix. Highlights Two model updated chemometric models called PCA and PLS were established for determination of prednisolone and esomeprazole in spiked human plasma using UV spectrophotometric data.

Development and Validation of a Method for Quantification of Favipiravir as COVID-19 Management in Spiked Human Plasma

In the current work, a simple, economical, accurate, and precise HPLC method with UV detection was developed to quantify Favipiravir (FVIR) in spiked human plasma using acyclovir (ACVR) as an internal standard in the COVID-19 pandemic time. Both FVIR and ACVR were well separated and resolved on the C18 column using the mobile phase blend of methanol:acetonitrile:20 mM phosphate buffer (pH 3.1) in an isocratic mode flow rate of 1 mL/min with a proportion of 30:10:60 %, v/v/v. The detector wavelength was set at 242 nm. Maximum recovery of FVIR and ACVR from plasma was obtained with dichloromethane (DCM) as extracting solvent. The calibration curve was found to be linear in the range of 3.1–60.0 µg/mL with regression coefficient (r2) = 0.9976. However, with acceptable r2, the calibration data’s heteroscedasticity was observed, which was further reduced using weighted linear regression with weighting factor 1/x. Finally, the method was validated concerning sensitivity, accuracy (Inter and Intraday’s % RE and RSD were 0.28, 0.65 and 1.00, 0.12 respectively), precision, recovery (89.99%, 89.09%, and 90.81% for LQC, MQC, and HQC, respectively), stability (% RSD for 30-day were 3.04 and 1.71 for LQC and HQC, respectively at −20 °C), and carry-over US-FDA guidance for Bioanalytical Method Validation for researchers in the COVID-19 pandemic crisis. Furthermore, there was no significant difference for selectivity when evaluated at LLOQ concentration of 3 µg/mL of FVIR and relative to the blank.

Green Sensitive Spectrofluorimetric determination of Remdesvir, an FDA approved SARS-COV-2 Candidate Antiviral; Application in Pharmaceutical Dosage Forms and Spiked Human Plasma

Fluorescent Spectroscopy has gained lots of interests pending the last years. Its advantages cover both; the analytical performance, as well as ecological greenness. The quality control of pharmaceuticals requires sensitive,...