Smart Chemometric­Assisted Spectrophotometric Approaches for Simultaneous Quantification of Tertiary Combination Recommended for COVID-19 Supportive Treatments with Their Greenness Assessment.

BACKGROUND: There is an increasing interest of scientific community in developing innovative methodologies for their analysis needs within green analytical chemistry framework. UV spectrophotometry is one of the most promising eco-friendly methods, which is integrated with advanced chemometric tools to enhance the selectivity of the analysis of complex mixtures with severe overlapped signals. OBJECTIVES: Simultaneous determination of a triple-combination of pseudoephedrine hydrochloride (PSE), carbinoxamine maleate (CRX), and paracetamol (PAR) using an artificial intelligence system and multivariate calibration methods. This combination is recently recommended for COVID-19 home-treated patients as part of a symptomatic treatment. METHODS: Namely, the suggested models are: Artificial Neural Networks, Partial Least Squares, and Principal Component Regression. The proposed algorithms were optimized and developed with the aid of a five-level, three-factor experimental design. RESULTS: The investigated methods were applied over the concentration range of 100-180 µg/mL, 18-16 µg/mL, and 4-12 µg/mL for PSE, CRX, and PAR, respectively. The models validation results demonstrated excellent recoveries (around 98 to 102%), signaling the approaches outstanding resolution capacity for the cited compounds in the presence of common excipients. The outcomes of the studied methods were statistically compared to the official approaches, and no significant difference was found. CONCLUSION: The suggested models were efficiently employed to determine the selected drugs in their combined tablets without any initial separation steps. The impact of these methods on the environment was evaluated via greenness tools, namely; National Environmental Method Index, Raynie and Driver's green assessment method, analytical Eco-Scale, Green Analytical Procedure Index, and Analytical Greenness Metric. HIGHLIGHTS: Green chemometric quality assessment of PSE, CRX, and PAR in their pure and pharmaceutical dosage forms. The established approaches are innovative, sustainable, smart, fast, selective, and cost-effective. These models are potential green nominees for routine analysis of the investigated mixture in quality control laboratories.

Biocontrol of multi-drug resistant pathogenic bacteria in drainage water by locally isolated bacteriophage.

In areas with limited water resources, the reuse of treated drainage water for non-potable purposes is increasingly recognised as a valuable and sustainable water resource. Numerous pathogenic bacteria found in drainage water have a detrimental impact on public health. The emergence of antibiotic-resistant bacteria and the current worldwide delay in the production of new antibiotics may make the issue of this microbial water pollution even more challenging. This challenge aided the resumption of phage treatment to address this alarming issue. In this study, strains of Escherichia coli and Pseudomonas aeruginosa and their phages were isolated from drainage and surface water from Bahr El-Baqar and El-Manzala Lake in Damietta governorate, Egypt. Bacterial strains were identified by microscopical and biochemical examinations which were confirmed by 16 S rDNA sequencing. The susceptibility of these bacteria to several antibiotics revealed that most of the isolates had multiple antibiotic resistances (MAR). The calculated MAR index values (> 0.25) categorized study sites as potentially hazardous to health. Lytic bacteriophages against these multidrug-resistant strains of E. coli and P. aeruginosa were isolated and characterized. The isolated phages were found to be pH and heat stable and were all members of the Caudovirales order as recognized by the electron microscope. They infect 88.9% of E. coli strains and 100% of P. aeruginosa strains examined. Under laboratory conditions, the use of a phage cocktail resulted in a considerable reduction in bacterial growth. The removal efficiency (%) for E. coli and P. aeruginosa colonies increased with time and maximized at 24 h revealing a nearly 100% reduction after incubation with the phage mixture. The study candidates new phages for detecting and controlling other bacterial pathogens of public health concern to limit water pollution and maintain adequate hygiene.

Novel Spectrophotometric Approaches for the Simultaneous Quantification of Ternary Common Cold Mixture Containing Paracetamol with a Challenging Formulation Ratio: Greenness Profile Evaluation.

BACKGROUND: Common cold and cough preparations represent a huge segment of the global pharmaceutical market. Recently, cold/cough formulations containing paracetamol (PAR) have attracted significant attention as PAR has been implemented into the supportive treatment of mild cases of COVID-19 as the first-line antipyretic. From a literature review, no method has been reported yet for simultaneous estimation of PAR, pseudoephedrine hydrochloride (PSE) and carbinoxamine maleate (CRX) in any matrix. Thus, there is an urgent need for smart and green methods that would enable quantification of the cited components in their challenging ratio. OBJECTIVES: The aim of this work is to develop and validate the first UV spectrophotometric methods for simultaneous determination of the selected drugs taking into consideration the list of challenges including the highly overlapping features and spectral interferences in the cited mixture. METHODS: Namely, the proposed methods are: direct spectrophotometry, dual wavelength, first derivative, derivative ratio, ratio difference, constant center coupled with spectrum subtraction, and the constant multiplication method paired with spectrum subtraction. RESULTS: These methods were linear over the concentration range of 2.5-35, 1.5-20, and 4.5-35 µg/mL for PAR, PSE and CRX, respectively. These methods fulfill the validity parameters according to International Conference on Harmonization (ICH) guidelines. The results obtained were statistically benchmarked to the official ones where no significant difference was noticed. CONCLUSION: The developed methods are successfully applied for concurrent quantification of the studied components in the marketed dosage form without interference from matrix excipients. The impact on the environment was assessed by five green metrics, namely a recent Analytical greenness (AGREE) metric algorithm based on the green analytical chemistry framework, Green Analytical Procedure Index (GAPI), Eco-Scale, Assessment of Green Profile (AGP), and National Environmental Methods Index (NEMI). HIGHLIGHTS: Eco-friendly and successive spectrophotometric methods were firstly developed in this work, for the simultaneous quantification of PAR, PSE and CRX. These approaches incorporate a simple enrichment-aided technique to augment their spectrophotometric signals, facilitating the accurate quantitation of the minor component in the cited mixture.

Stability study of thymoquinone, carvacrol and thymol using HPLC-UV and LC-ESI-MS.

The aim of this study was to investigate the stability of three major antioxidants of Nigella sativa: thymoquinone (TQ), carvacrol (CR) and thymol (THY), under different stress conditions using HPLC and LC-MS/MS. Forced degradation for each compound was performed under different conditions, including oxidation, hydrolysis, photolysis and thermal decomposition. The results showed that both CR and THY were stable under the studied conditions, whereas TQ was not affected by acidic, basic and oxidative forced conditions but the effect of light and heat was significant. The degradation products of TQ were further investigated and characterized by LC-MS/MS. HPLC-UV method has been fully validated in terms of linearity and range, the limit of detection and quantitation, precision, selectivity, accuracy and robustness. The method was successfully applied to quantitative analysis of the principal antioxidants of Nigella sativa TQ, CR and THY in different phytopharmaceuticals.

HPLC-DAD determination of seven antioxidants and caffeine in different phytopharmaceuticals.

A high-performance liquid chromatography method employing diode array detection was developed to determine levels of the major catechins, proanthocyanidin (procyanidin B2), caffeine, thymoquinone and carvacrol and its isomer, thymol, which are present in different natural complex matrices found in commercial products of Camellia sinensis L. and/or Nigella sativa L. Reversed-phase separation was performed on a C18 column by using gradient elution by varying the proportions of solvent A (distilled water containing 0.05% orthophosphoric acid) and solvent B (acetonitrile), with a flow rate of 1.5 mL/min and duration of 31 min. Excellent linearity was observed for all standard calibration curves, and correlation coefficients were above 0.9996. The developed method is efficient, with high reproducibility and sensitivity, and is ideally suited for rapid and routine analysis of principal components in these promising medicinal plants.

Rapid and simultaneous determination of antioxidant markers and caffeine in commercial teas and dietary supplements by HPLC-DAD.

A simple and fast reverse-phase high-performance liquid chromatography procedure coupled with photodiode array detector (RP-HPLC-DAD) was developed and validated for the analysis of major catechins, proanthocyanidin (procyanidin B2) and caffeine in 25 different natural complex matrices containing Camellia sinensis L. and/or grape seed extracts, two popular plant extracts that have been widely used as natural antioxidants in various food and beverage applications. Using an isocratic elution system, separation of all compounds was achieved within 12 min. Excellent linearity was observed for all of the standard calibration curves, and the correlation coefficients were above 0.9997. Limits of detection for all of the analyzed compounds ranged between 2.80×10(-3) and 2.51×10(-2) µg mL(-1); limits of quantitation ranged between 9.30×10(-3) and 8.36×10(-2) µg mL(-1). The developed method was found to be accurate and sensitive and is ideally suited for rapid, routine analysis of principal components in these well-known natural antioxidants.

High-performance liquid chromatography quantification of principal antioxidants in black seed (Nigella sativa L.) phytopharmaceuticals.

A new, simple, sensitive, rapid, and accurate isocratic RP-HPLC method was developed and validated for simultaneous analysis of the principal antioxidants of Nigella sativa, i.e., thymoquinone (TQ), carvacrol (CR), and its isomer thymol (THY), in different phytopharmaceuticals. The mobile phase was water-methanol (40 + 60, v/v) at a flow rate of 1.5 mL/min. Quantification was achieved with UV detection at 254 nm, based on peak area. The method was validated for linearity, accuracy, precision, selectivity, and robustness. The proposed method is stability-indicating for determination of TQ in the presence of its degradants. The LOD and LOQ (microg/mL) were, respectively, 0.006 and 0.021 for TQ, 0.002 and 0.006 for CR, and 0.027 and 0.090 for THY. The mean recoveries measured at three concentrations were higher than 99%, with RSD <2%. This analytical method is suitable for quality control of the marker substances in this widely used natural protective and curative remedy.