Rapid One-Pot Microwave Assisted Green Synthesis Nitrogen Doped Carbon Quantum Dots as Fluorescent Precursor for Estimation of Modafinil as Post-Covid Neurological Drug in Human Plasma with Greenness Assessments.

The neuro-stimulant anti-narcoleptic drug as modafinil (MOD) is used to treatment neurological conditions caused by COVID-19. MOD was used to treatment narcolepsy, shift-work sleep disorder, and obstructive sleep apnea-related sleepiness. So, an innovative, quick, economical, selective, and ecologically friendly procedure was carried out. A highly sensitive N@CQDs technique was created from green Eruca sativa leaves in about 4 min using microwave synthesis at 700 w. The quantum yield of the synthesized N@CQDs was found to be 41.39%. By increasing the concentration of MOD, the quantum dots' fluorescence intensity was gradually quenched. After being excited at 445 nm, the fluorescence reading was recorded at 515 nm. The linear range was found to be in the range 50 - 700 ng mL-1 with lower limit of quantitation (LOQ) equal to 45.00 ng mL-1. The current method was fully validated and bio analytically according to (US-FDA and ICH) guidelines. Full characterization of the N@CQDs has been conducted by high resolution transmission electron microscope (HRTEM), Zeta potential measurement, fluorescence, UV-VIS, and FTIR spectroscopy. Various experimental variables including pH, QDs concentration and the reaction time were optimized. The proposed study is simply implemented for the therapeutic drug monitoring system (TDMS) and various clinical laboratories for further pharmacokinetic research.

Zinc(II) complexation strategy for ultra-sensitive fluorimetric estimation of molnupiravir: Applications and greenness evaluation.

The endemicity of the pandemic coronavirus disease 2019 (COVID-19) infection proved to be transitional only. Spikes are forming again in 2023, and high expectations are returning for reinfections and viral mutations. Molnupiravir (MOL) has been approved as an oral antiviral drug for the treatment of the COVID-19 causative virion. Therefore, the development of an ultrasensitive, instantaneous, and cost-effective method for the quantification of MOL in real plasma samples and formulated dosage form are mandatory. The proposed approach is based on the synthesis of a MOL metal-chelation product. MOL as a ligand was chelated with 1.0 mM zinc(II) in an acetate buffer (pH 5.3). After illumination at 340 nm, the intensity of the MOL fluorescence measured at 386 nm was increased by about 10-fold. The linearity range was found to be from 60.0 to 800.0 ng mL-1 with limit of quantitation (LOQ) of 28.6 ng mL-1 . Two methods were utilized for measuring the greenness of the proposed method (Green Analytical Procedure Index [GAPI] and analytical greenness metric [AGREE] methods), with results equal to 0.8. The binding stoichiometry of MOL with the zinc(II) ion was found to be 2:1. All the experimental parameters were optimized and validated using International Conference on Harmonization (ICH) and United States Food and Drug Administration (US-FDA) recommendations. Furthermore, the fluorescent probes were successfully utilized in real human plasma with high percentages of recovery (95.6%-97.1%) without any matrix interferences. The mechanism of fluorescent complex formation was confirmed using 1 H NMR in the presence and absence of Zn(II). The method was further utilized for testing content uniformity of MOL in its marketed capsule dosage forms.

An Innovative Polymer-Based Electrochemical Sensor Encrusted with Tb Nanoparticles for the Detection of Favipiravir: A Potential Antiviral Drug for the Treatment of COVID-19.

An innovative polymer-based electro-sensor decorated with Tb nanoparticles has been developed for the first time. The fabricated sensor was utilized for trace determination of favipiravir (FAV), a recently US FDA-approved antiviral drug for the treatment of COVID-19. Different techniques, including ultraviolet-visible spectrophotometry (UV-VIS), cyclic voltammetry (CV), scanning electron microscope (SEM), X-ray Diffraction (XRD) and electrochemical impedance spectroscopy (EIS), were applied for the characterization of the developed electrode TbNPs@ poly m-THB/PGE. Various experimental variables, including pH, potential range, polymer concentration, number of cycles, scan rate and deposition time, were optimized. Moreover, different voltammetric parameters were examined and optimized. The presented SWV method showed linearity over the range of 10-150 × 10-9 M with a good correlation coefficient (R = 0.9994), and the detection limit (LOD) reached 3.1 × 10-9 M. The proposed method was applied for the quantification of FAV in tablet dosage forms and in human plasma without any interference from complex matrices, obtaining good % recovery results (98.58-101.93%).

Fabrication of novel quantum dots for the estimation of COVID-19 antiviral drug using green chemistry: application to real human plasma† † Electronic supplementary information (ESI) available. See https://doi.org/10.1039/d2ra02241a

The COVID-19 pandemic has encouraged the search for novel antiviral medications. Recently, molnupiravir (MOL) has been approved as an oral antiviral to manage COVID-19. Thus, the development of sensitive and cost-effective methods for quantification of MOL in real plasma samples (pharmacokinetic) and pharmaceutical tablets is required. Herein, we present the fabrication of novel fluorescent polyamine quantum dots (PA@CQDs) fabricated from apricots using one step synthesis for analysis of MOL. The relative fluorescence intensity (RFI) of the synthesized quantum dots was influentially quenched by the addition of molnupiraivr. The linear range was found to be between 2–70 ng mL−1 with lower limit of quantitation (LOQ) equal to 1.61 ng mL−1. The fluorescent probe was successfully utilized in a pharmacokinetic study of MOL with maximum plasma concentration (Cmax) 920.2 ± 6.12 ng mL−1 without any matrix interference. The sensitivity and selectivity of the presented method allow its application in clinical laboratories. A novel, selective and sensitive fluorimetric method for determination of MOL using PA@QDs in real human plasma and pharmaceutical formulation.

Fabrication of novel quantum dots for the estimation of COVID-19 antiviral drug using green chemistry: application to real human plasma.

The COVID-19 pandemic has encouraged the search for novel antiviral medications. Recently, molnupiravir (MOL) has been approved as an oral antiviral to manage COVID-19. Thus, the development of sensitive and cost-effective methods for quantification of MOL in real plasma samples (pharmacokinetic) and pharmaceutical tablets is required. Herein, we present the fabrication of novel fluorescent polyamine quantum dots (PA@CQDs) fabricated from apricots using one step synthesis for analysis of MOL. The relative fluorescence intensity (RFI) of the synthesized quantum dots was influentially quenched by the addition of molnupiraivr. The linear range was found to be between 2-70 ng mL-1 with lower limit of quantitation (LOQ) equal to 1.61 ng mL-1. The fluorescent probe was successfully utilized in a pharmacokinetic study of MOL with maximum plasma concentration (C max) 920.2 ± 6.12 ng mL-1 without any matrix interference. The sensitivity and selectivity of the presented method allow its application in clinical laboratories.

Highly sensitive high-performance thin-layer chromatography method for the simultaneous determination of molnupiravir, favipiravir, and ritonavir in pure forms and pharmaceutical formulations.

Favipiravir, molnupiravir, and ritonavir have been recently approved as the first oral antivirals for treatment of SARS-CoV-2 viral infections. Their combination was reported in several clinical studies, alternatively, to enhance the viral eradication and improve patient's recovery times and rates. Being all orally administered, therefore, the development of new sensitive and validated methodologies for their simultaneous determination is a necessitate. In the proposed research, a sensitive, selective, and simple high-performance thin layer chromatography method was developed and validated for determination of favipiravir, molnupiravir, and ritonavir. Silica gel 60F254 thin layer chromatography plates were used as stationary phase for this separation using mobile phase composed of methylene chloride:ethyl acetate:methanol:25% ammonia (6:3:4:1, v/v/v/v). Densitometric detection was performed at wavelength 289 nm. Peaks of favipiravir, molnupiravir, and ritonavir were resolved at retention factors 0.22, 0.42, and 0.63, respectively. The proposed method was found linear within the specified ranges of 3.75-100.00 µg/mL for molnupiravir and favipiravir, and 2.75-100.00 µg/mL for ritonavir. Limits of detection were found to be 1.12, 1.21, and 0.89 µg/mL for favipiravir, molnupiravir, and ritonavir, respectively. This is the first method to be reported for the simultaneous determination of the cited three antiviral drugs. The method was assessed on novel greenness metrics.