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Background:: The drug's affinity to the identified target (protein/enzyme) is a critical characteristic in the development of a novel drug. Fluoroquinolone derivatives with a carboxylic group change have improved antimicrobial and anticancer activity while maintaining antibacterial activity similar to parent drugs. Aim:: The rationale upon which synthesis of the new compounds, evaluation of their anticancer activity with in silico study, and suggestion of their mechanism of action is presented in this paper. Methods:: This part describes the practical procedures used for the synthesis of four new gatifloxacin 3-carboxamide derivative, with their spectral data (UV-vis, IR, and 1H-NMR). The enantiosaparation and docking studies are presented and discussed. Results:: Four gatifloxacin 3-carboxamide derivatives were enantioseparated using a high-performance liquid chromatography approach using two distinct polysaccharide-based chiral stationary phases (CSPs). The baseline enantioseparation of all derivatives evaluated in this study was achieved using both coated and immobilized amylose columns. In silico molecular docking study, revealed that all compounds showed good docking score. Conclusion:: The novel Fluoroquinolone caboxamides derivatives could be repositioned as DNA topoisomerase II inhibitors, allowing them to be employed as anticancer agents, according to our in silico study. Experiments in vitro and in vivo are required to confirm their efficacy.

Objective: Linezolid is a significant antibiotic used against severe infections initiated by multi-resistant bacterial pathogens. Method: The aim of this study is to develop and validate a simple, selective and accurate highperformance liquid chromatographic HPLC method for the analysis of linezolid LZD. Method: Linezolid extraction from plasma is obtained using methanol. Chromatographic separation is achieved isocratically on a C18 column [Zorbax C18, 5 μm particle size, 150 mm˟ 4.6 mm] making use of a mobile phase of acetonitrile / 0.05 M phosphate buffer, pH = 4.5 (30: 70 v/v) at a flow rate of 1.2 mL/min with photodiode array detector DAD, at a wavelength of 256 nm. Results : The retention time of linezolid was 2.5 min. The analytical method was linear (r2 > 0.998) over the calibration range of 0.30 to 50.0 μg/mL. The extraction recoveries of linezolid range from 71.03 to 91.93 %. The limit of quantification and the limit of detection were 0.112 μg and 0.037 μg, respectively. The RSDs for intraday and interday assays were < 7.77 and 4.32 %, respectively. The intraday and interday accuracies were in the range 80.6-112 % and 77.44- 104.85 %, respectively. Conclusion: The applied method is precise, accurate and appropriate for pharmacokinetic studies and therapeutic drug monitoring of linezolid in routine clinical practice.

Hepatitis C virus is very common amongst population infected with viral hepatitis. A very important point before deciding on the correct treatment is the stage of illness. More people are detected too late, and therefore the treatment was not efficient. A highly sensitive and selective screening system for early detection is needed in order to cure the patient cured. Therefore, this review is summarizing new methods of detection of specific biomarkers/genotypes for viral hepatitis C, to help find the highest sensitive screening methods that may influence the decision of the most efficient treatment.

The impact of repurposing drugs that now in vitro inhibit significant chronic respiratory illness corona virus type 2 was indeed underestimated or ignored during the early phases of the COVID-19 virus. Recent clinical data, however, suggest that remdesivir and favipiravir may hasten to heal, but lopinavir/ritonavir had minimal impact on very ill patients. The interferon appears to be the primary impact of triple therapy with ribavirin, lopinavir and interferon-1b. The role of hydroxychloroquine, marketed as Plaquenil® or chloroquine, marketed as Aralen®, in the treatment and prevention of COVID-19 is presently unknown due to the small sample size research. Anti-cytokine drugs may not benefit persons with mild disease or severe illness. Traditional Chinese medicine (TCM) is commonly used for COVID-19 patients in China and has antiviral and immunomodulatory effects on SARS-CoV-2. This review outlines existing COVID-19 therapeutic options and advocates for clinical trials for children, persons with mild disease and those in the early stages of COVID-19.

Abstract: The recent development of monolithic chiral stationary phases (CSPs) for liquid chromatography (LC) is mainly focused on reducing backpressure, maximizing flow rates, faster run time, column efficiency, and stability. This review paper emphasizes recent progress in the development of polysaccharide and cyclodextrin-based monolithic CSPs. Further the paper draws attention to competing techniques, like non-porous particle-packed columns, core-shell and monoliths as chromatographic support matrix, available for achieving fast and efficient chromatographic separation. A brief discussion on the three main classes of chiral monolithic stationary phase viz. silica, organic polymer and hybrid-based monolithic stationary phases is also presented. In addition, the paper highlights various studies on the application of monolith chiral CSPs in LC and capillary electrochromrography separation and analysis of chiral compounds.

Abstract: 2-Arylpropionic acid nonsteroidal anti-inflammatory drugs (NSAIDs) provide one of the most demonstrated pharmaceutical examples of chiral inversion. Chiral inversion depends on various factors (viz. biological-, solvent-, light-, temperature-induced, etc.) and the energy barrier associated with the stereogenic element present in the chiral molecule. The pharmacological properties of chiral drugs depend on the activity of one enantiomer or both the enantiomers targeting different biological targets. Consequently, chiral inversion can alter the biological activities of the pharmaceutical drug. Hence a better understanding of chiral inversion, factors facilitating such inversion, and the tools employed to determine chiral inversion are of great significance from a pharmacological and toxicological perspective.

The development of chiral selectors for the separation and analysis of chiral molecules has been an evolving process happening over three decades, since the introduction of the first chiral stationary phase (CSP) in 1938. The main impetus for designing new chiral selectors is to get to most promising one which has a broad chiral recognition property, separation capability for a wide range of chiral analytes, and the cost-effective CSP, which is also a major concern. Today, we have more than 100 commercially available CSPs, and these are prepared by coating or immobilizing the classical chiral selectors on to the chromatographic support, normally, silica gel. The purpose of this review is to look at progress and the impact of cyclofructan derivatives, a novel chiral selector introduced recently, for performing chiral analysis.

Non-biodegradable plastics are an unresolved issue in solid waste management as recycling them is expensive. This study focused on formulating a biodegradable gellan gum (GG) membrane embedded with multiwalled carbon nanotubes (MWCNTs) as the adsorbent in the micro-solid phase extraction (µ-SPE) of selected polycyclic aromatic hydrocarbons (PAHs), i.e. phenanthrene, fluoranthene, pyrene and benzo[a]pyrene, in environmental water and fruit-juice beverage samples. PAHs quantitation was performed using micro-high-performance liquid chromatography coupled with ultraviolet detection. The MWCNTs GG membrane was fabricated by mixing MWCNTs in a hot GG solution, which was then crosslinked with glutaraldehyde to resist membrane swelling during extraction. Under the optimal extraction conditions, the proposed µ-SPE technique demonstrated good linearity (1–500 µg L−1; correlation coefficient of ≥ 0.9925) and ultra-trace detection limits (10–60 ng L−1). Good relative recoveries in the range of 81.3–114.9% with acceptable relative standard deviations (≤ 9.7%) revealed that matrix effects were insignificant because the MWCNTs-GG membrane-based µ-SPE offered a clean extract in these real samples. The proposed µ-SPE technique is proven to be sensitive, accurate and green with an analytical eco-scale score of 81, which supports green analysis for a better tomorrow.

Warionia saharae Benth & Coss (W.s) (Asteraceae) is a monospecific genus endemic to Algeria and Morocco. Its leaves are used in their traditional medicine, such as gastrointestinal and inflammatory diseases; for instance, rheumatoid arthritis treatment. In this work, our team investigated the anti-inflammatory and analgesic effects of essential oil extracted from the dried upper parts of Warionia saharae based on different standard experimental test models. The analgesic activity was assessed by central and peripheral models, such as “hot plate” and “writhing” tests on Swiss albino mice. The hot plate test used latency measurements to assess acute cutaneous pain sensitivity, as a result; the latency of the hind-paw pain response was by licking and either shaking or jumping, those occurrences were recorded. Writhing test as a chemical method used to induce pain of peripheral origin in mice by injecting acetic acid intraperitoneally (IP). This results in characteristic stretching behavior of the animals (cramps and contortions). The evaluation of the analgesic activity, shows that the essential oil of this plant induces a decrease in the number of abdominal cramps in the contortion test and a maximum inhibition of pain. As for the anti-inflammatory effect, it was studied by the “paw edema” test, a phlogogenic agent (formaldehyde) was used to stimulate inflammation in the paws of mice. Anti-inflammatory properties can be observed by inhibiting this edema compared to the standard drug Diclofenac. In conclusion, Warionia saharae essential oil (75 mg/kg) showed a strong anti-inflammatory and analgesic activities which supports the conventional use of this plant in traditional medicine.

A sample preparation method based on modified Quick, Easy, Cheap Effective, Rugged, and Safe (QuEChERS) and GC–MS method was developed and validated for identification and quantification of amphetamine (AP), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), and 3,4-methylenedioxymethamphetamine (MDMA) in human urine. Several derivatization parameters such as derivatization temperature, time, and volume of derivatizing agent were optimized. dSPE parameters were optimized. Under the optimized conditions, the method was validated with respect to selectivity, linearity, limits of detection and quantification, precision, accuracy, and recoveries. Linearity was obtained in the concentration range of 50–1200 ng/mL for all the drugs. The intra- and inter-day precision and accuracy were acceptable. The RSD values ranging from 0.08 to 3.43% and 0.23% to 3.0% for intra- and inter-day precision were obtained, respectively. Accuracy was within the required limits (± 15% and ± 20% at LOQ) for all analytes at three concentrations studied. Analyte recoveries that ranged from 87.8 to 95% were obtained. These figures resulted within the best recovery percentages as comparing with the previous studies. The method was successfully applied to the routine work of the Sudanese Forensic laboratories to detect and quantify the AP, MA, MDA, and MDMA in urine samples.

Background: Indole-3-acetic acid (IAA) is an important growth hormone for plants obtained by biosynthesis from tryptophan. Aim: In this paper was studied the competitive transport of two biologically active compounds, indole-3-acetic acid (IAA) and tryptophan (TRP) through a liquid membrane. Methods: The separation of the two compounds was obtained using a hybrid liquid membrane system having as a carrier trioctylphosphine oxide (TOPO). Results: The most important operational parameter of the system were studied, pH influence on the efficiency of the transport process in correlation with the speciation diagrams of the two compounds: TRP and IAA. The evaluation of the transport process was performed through calculating the composition of the phases at the end of the transport process and the organic substrate flow at the membranes exit. Conclusion: Due to the transport efficiency of over 90% in the case of IAA and the high selectivity at the transport between IAA and TRP, the procedure can be applied at the sample preparation containing these analytes.

Three chiral pyrazoline derivatives were synthesized by a flavanone ring-opening reaction followed by cyclocondensation with hydrazine hydrate to give better yields. Their enantiomeric resolution was achieved using polysaccharide chiral stationary phase columns consisting of cellulose (Chiralcel®OD-RH, Chiralcel®OZ-3) and amylose (Chiralpak®IA) by high-performance liquid chromatography. The separation was affected by the nature and concentration of the alcohol modifiers in the mobile phase. Taking 5-methoxy-2-(3-phenyl-4,5-dihydro-1H-pyrazol-5-yl)phenol (3a) as an example, the best separation was obtained by using the Chiralpak®IA column, with a separation factor α = 1.24 and Rs = 5.66 within an analysis time of30 min. The diarylpyrazolines showed good antioxidant activity, studied by the DPPH method.

In this work, enantiomeric separation of a drug combination of two chiral drugs, namely, atenolol and chlorthalidone, is described. Prior investigation of the effect of different variables on the resolution of the enantiomers' peaks and the total run time represented by the retention time of the last eluted peak was conducted using face-centered composite design. Twenty-two experiments were carried out by varying the chiral stationary phase type as a categorical factor and mobile phase composition including the percentage of ethanol and percentage of diethylamine as continuous factors. According to the optimization process, a mobile phase consisting of hexane:ethanol:DEA:TFA (60:40:0.2:0.1%, v/v/v/v) pumped at flow rate 1 ml min-1 onto Lux-Cellulose 2 stationary phase was applied for the chiral separation and quantification of the drug combination at 230 nm. Application of the developed method to the pharmaceutical formulation of this combination was successfully performed, and satisfactory percentage of recoveries was obtained. The method was also fully validated following International Conference on Harmonization (ICH) guidelines. This method could be of high value and relevance for application in quality control laboratories.

Synthesis of three chiral 4,5-Di methyl ∆4 N-phenyl N-aryl imidazole-2-thione derivatives was obtained by the condensation reaction of thiourea derivatives with α-hydroxy ketone. The structure of these compounds has been characterized by using spectroscopic methods (UV, IR, 1 H NMR, and 13 C NMR). The 4,5-Di methyl ∆4 N-phenyl N-aryl imidazole-2-thiones display a chiral axis around the N-C bond linking between the nitrogen of the heterocyclic framework and the carbon of the aryl group. Screening on chiral analysis of the atropisomers of these derivatives was performed by high-performance liquid chromatography method on seven chiral selectors based on polysaccharides consisting of amylose and cellulose, namely, Chiralpak®AD, Chiralcel® OD, Chiralcel® OD-H, Chiralcel® OJ, Chiralcel® OD-3R, Chiralcel® OZ-3, and Chiralpak® AS-3R. The impact of ortho-substituent in the resolution of 4,5-Di methyl ∆4 N-phenyl N-aryl imidazole-2-thione derivatives was also studied in this work.

2D-HPLC is an important development in chiral separations due to its excellent capability to resolve the enantiomers. This article describes the latest update in the chiral resolution of racemates using 2D-HPLC. The various aspects of the chiral resolution such as validation, optimization, and applications are discussed in both biological and environmental matrices. Some latest developments of nano-2D-HPLC are also included. Besides, efforts are made to discuss the challenges and future perspectives. During the preparation of this article, it was observed that much work has not been done in this direction and only a few papers describe the application of 2D-HPLC in the chiral separation. There is an urgent need to develop more 2D-HPLC methods for a variety of racemates. This article will be useful to the investigators, academicians and industry persons in the future to improve 2D-HPLC for the chiral resolution of the various racemates.

Adsorbent-based microextraction is a dynamic and simple sample preparation that allows for simultaneous extraction and enrichment of targeted analytes from a sample matrix. Its versatility, efficiency, and compliance with green analysis have contributed to its popularity against conventional solid-phase extraction. This review focuses on the current state of the art, future trends in experimental design, and critical aspects of adsorbent-based microextraction techniques considered for extraction and preconcentration of different classes of micropollutants in environmental waters. Despite solid-phase microextraction has shown exceptional flexibility in routine microscale extraction, the other adsorbent-based microanalytical work continues to experience an enormous increase in innovation. Discussions are focused on recent studies utilizing different modes include dispersive, magnetic, bar sorptive, membrane-protected, and thin film for introducing adsorbents in an aqueous media. Cogently, the developed micro-scale procedure using functionalized adsorbent has shown distinct advantages over conventional methods. Modifications were aimed at shortening the time for analysis, minimal waste production, and robustness over the complexity of sample matrices. Adsorbent selection is now widening from commercial materials like activated carbon to newly synthesized materials such as metal-organic framework. The final section discusses the current progress on hybrid approaches and the intended future directions to further explore and popularize the adsorbent-based microextraction. This review guides the audiences with an introductory, succinct discussion of the basic concepts of the adsorbent-based microextraction and the success story of the high-throughput real sample analysis.

Chiral molecules in relation to particular biological roles are stereoselective. Enantiomers differ significantly in their biochemical responses in biological environment. Despite the current advancement in drug discovery and pharmaceutical biotechnology, the chiral separation of some racemic mixtures continues to be one of the greatest challenges, because the available techniques are too costly and time consuming for the assessment of therapeutic drugs in the early stages of development worldwide. Various nanoparticles became one of the most investigated and explored nanotechnology-derived nanostructures especially in chirality where several studies are reported to improve enantiomeric separation of different racemic mixtures. The production of surface-modified nanoparticles has contributed to these limitations in terms of sensitivity, accuracy, and enantioselectivity that can be optimized and therefore makes these surface-modified nanoparticles convenient for enantiomeric identification and separation.

A thionation reaction was performed on some chiral flavanones using Lawesson’s reagent (LR) and leads to the formation of new chiral thiocarbonyl flavanes. LR in this thionation reaction with Hesperetin and Naringenin gives new flavan-4-thiones with yields ranged between 41 and 52%. Based on the Wittig reaction principle, LR is currently the most widely used reagent for this type of reaction. Enantiomeric separation by high-performance liquid chromatography methods was then set-up using three different polysaccharide-based chiral stationary phases (CSPs). Chiral separations were successfully accomplished with high resolution (1.22 ≤ Rs ≤ 5.23). The chiral discrimination mechanism(s) between the analytes under study, mobile phase, and the CSPs were discussed.

Recent success in studying the proteome, as a source of biomarkers, has completely changed our understanding of leukemia (blood cancer). The identification of differentially expressed proteins, such as relapse and drug resistance proteins involved in leukemia by using various ionization sources and mass analyzers of mass spectrometry techniques, has helped scientists find better diagnosis, prognosis, and treatment strategies. With the aid of this powerful analytical technique, we can investigate the qualification/quantification of proteins, protein-protein interactions, post-translational modifications, and find the correlation between proteins and their genes with the hope of finding the missing parts of the successful therapy puzzle. In this review, we followed different MS sources and analyzers which used for monitoring various type of leukemia, then focused on MALDI-TOF MS as a quick and reliable method for studying proteins. Due to several review published for other techniques, the present review is the first work in this field. Also, by classifying more than 400 proteins, we have found 42 proteins are involved in two or three different stages of leukemia. Finally, we have suggested six specific biomarkers for AML, one for ALL, three biomarkers with a role in the etiology of leukemia and 13 markers with the potential for further studies.

Fluopyram, flupyradifurone, and indaziflam are novel systemic pesticides developed by Bayer. Based on available data, these pesticides appears to have a favorable safety profile in the case of pest...

In this study, a new type of multifunctional material PANI/NiO/MnO2 nanocomposite was first time prepared by chemical polymerisation from aniline monomer in the presence of metal oxides (NiO and MnO2) and an oxidant (ammonium persulfate) in acidic aqueous solution for the elimination of methyl orange (MO) dye from water. Herein, the PANI/NiO/MnO2 nanocomposite was found to be a favourable adsorbent for wastewater treatment due to its high adsorption and efficiency, self-regeneration, low cost and easy synthesis. Fourier transform infrared spectroscopy, X-ray diffraction, thermo-gravimetric analysis, transmission electron microscopy, scanning electron microscopy, Brunauer–Emmett–Teller analysis and Zeta potential were employed to characterise the synthesised nanocomposites. The data revealed that PANI nanocomposites doped with NiO and MnO2 nanoparticles had a higher adsorption efficiency (~ 97%) than that found in pure PANI (~ 53%). The adsorption conditions, such as pH of the medium, initial dye concentration, adsorbent dosage, and adsorption time were investigated. Various kinetic and isotherm models were used to analyse the results of the kinetics and the equilibrium adsorption and to interpret the interaction between the dye and nanocomposite adsorbents. The adsorption kinetics data for MO dye on the PANI/NiO/MnO2 were well explained based on a pseudo-second-order model while adsorption isotherm results were analysed based upon the Langmuir isotherm model. In addition, the adsorption process was an endothermic, favourable and spontaneous reaction according to thermodynamic studies. Also, the influence of matrix synthetic waste on MO dye removal was studied and found to show good results with matrix synthetic waste for both PANI/NiO/MnO2 and PANI adsorbents. The experimental adsorption capacity of the PANI/NiO/MnO2 nanocomposite (248.4 mg/g) was considerably greater than that of PANI (57.5 mg/g). The PANI/NiO/MnO2 adsorbent can be recycled up to four times and maintains a good adsorption capacity throughout.

Infrared spectroscopy has been used to more and more to characterize pharmaceutical products, even they are chemical substances or herbal, in order to monitor some modifications and to detect fraud...

Capacitively coupled contactless conductivity detection (C4D) has emerged as influential to detect analytes that do not have chromogenic or fluorogenic functional group. Since our last review sever...