RESUMO
Establishing sensitive and targeted analytical methodologies for drug identification in biological fluids as well as screening of treatments that can counteract the most severe COVID-19 infection-related side effects are of utmost importance. Here, first attempts have been made for determination of the anti-COVID drug Remdesivir (RDS) in human plasma using four potentiometric sensors. Calixarene-8 (CX8) was used as an ionophore applied to the first electrode (Sensor I). The second had a layer of dispersed graphene nanocomposite coating (Sensor II). (Sensor III) was fabricated using nanoparticles of polyaniline (PANI) as ion-to-electron transducer. A reverse-phase polymerization using polyvinylpyrrolidone (PVP) was employed to create a graphene-polyaniline (G/PANI) nanocomposite electrode (Sensor IV). Surface morphology was confirmed by Scanning Electron Microscope (SEM). UV absorption spectra and Fourier Transform Ion Spectrophotometry (FTIR) also supported their structural characterization. The impact of graphene and polyaniline integration on the functionality and durability of the manufactured sensors was examined using the water layer test and signal drift. In the ranges of concentration of 10-7 to 10-2 mol/L and 10-7 to 10-3, sensors II & IV exhibited linear responses; respectively while sensors I & III displayed linearity within 10-6 to 10-2 mol/L. The target drug was easily detectable using LOD down to 100 nmol/L. The developed sensors satisfactorily offered sensitive, stable, selective and accurate estimate of Remdesivir (RDS) in its pharmaceutical formulation as well as spiked human plasma with recoveries ranging from 91.02 to 95.76 % with average standard deviations less than 1.85. The suggested procedure was approved in accordance with ICH recommendations.
RESUMO
Since the emergence of Corona virus disease (COVID-19) in 2019, a number of medications have been developed and tried to combat the pandemic. In the present study, we develop a LC-MS/MS approach to detect and quantify certain COVID-19 candidate drugs in rat plasma, including Hydroxychloroquine, Favipiravir, Oseltamivir, and Remdesivir. The analytes were separated using Ultra High-Pressure Liquid Chromatography (UHPLC) over a 13-minute run on a C18 column. The extraction solvent for the (QuEChERS) quick, easy, cheap, effective, rugged and safe method was methanol, while the clean-up phase was primary secondary amine (PSA). Satisfactory recoveries were achieved for all compounds ranging from 82.39 to 105.87 %, with standard deviations smaller than 15.7. In terms of precision, accuracy, linearity, matrix effect, and stability, the method was validated according to US FDA criteria. The Limit of Detection (LOD) was determined to be between 0.11 and 10 ppb. The approach was further developed for a modest pharmacokinetic research in laboratory rats, and thus can be suitable for therapeutic drug monitoring in clinical cases under the same treatment.