Rapid and simple electrochemical detection of morphine on graphene–palladium-hybrid-modified glassy carbon electrode

A hybrid of reduced graphene oxide–palladium (RGO–Pd) nano- to submicron-scale particles was simultaneously chemically prepared using microwave irradiation. The electrochemical investigation of the resulting hybrid was achieved using cyclic voltammetry and differential pulse voltammetry. RGO–Pd had a higher current response than unmodified RGO toward the oxidation of morphine. Several factors that can affect the electrochemical response were studied, including accumulation time and potential, Pd loading, scan rate, and pH of electrolyte. At the optimum conditions, the concentration of morphine was determined using differential pulse voltammetry in a linear range from 0.34 to 12 μmol L^?1 and from 14 to 100 μmol L^?1, with detection limits of 12.95 nmol L^?1 for the first range. The electrode had high sensitivity toward morphine oxidation in the presence of dopamine (DA) and of the interference compounds ascorbic acid (AA) and uric acid (UA). Electrochemical determination of morphine in a spiked urine sample was performed, and a low detection limit was obtained. Validation conditions including reproducibility, sensitivity, and recovery were evaluated successfully in the determination of morphine in diluted human urine.

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Preclinical evaluation of 188 Re-HYNIC-PSMA as a novel therapeutic agent

Journal of Radioanalytical and Nuclear Chemistry - In this study, optimized preparation, quality control, cell assessments and biostribution of 188Re-HYNIC-PSMA in normal rats and tumor bearing...     

Preparation and dispersion stability of aqueous metal oxide nanofluids for potential heat transfer applications: a review of experimental studies

Journal of Thermal Analysis and Calorimetry - Nanofluids have recently attracted attention of many researchers due to their growing potential applications in heat transfer devices. They possess...     

Selenium Alleviates the Adverse Effect of Drought in Oilseed Crops Camelina (Camelina sativa L.) and Canola (Brassica napus L.)

Drought poses a serious threat to oilseed crops by lowering yield and crop failures under prolonged spells. A multi-year field investigation was conducted to enhance the drought tolerance in four genotypes of Camelina and canola by selenium (Se) application. The principal aim of the research was to optimize the crop yield by eliciting the physio-biochemical attributes by alleviating the adverse effects of drought stress. Both crops were cultivated under control (normal irrigation) and drought stress (skipping irrigation at stages i.e., vegetative and reproductive) conditions. Four different treatments of Se viz., seed priming with Se (75 μM), foliar application of Se (7.06 μM), foliar application of Se + Seed priming with Se (7.06 μM and 75 μM, respectively) and control (without Se), were implemented at the vegetative and reproductive stages of both crops. Sodium selenite (Na₂SeO₃), an inorganic compound was used as Se sources for both seed priming and foliar application. Data regarding physiochemical, antioxidants, and yield components were recorded as response variables at crop maturity. Results indicated that WP, OP, TP, proline, TSS, TFAA, TPr, TS, total chlorophyll contents, osmoprotectant (GB, anthocyanin, TPC, and flavonoids), antioxidants (APX, SOD, POD, and CAT), and yield components (number of branches per plant, thousand seed weight, seed, and biological yields were significantly improved by foliar Se + priming Se in both crops under drought stress. Moreover, this treatment was also helpful in boosting yield attributes under irrigated (non-stress) conditions. Camelina genotypes responded better to Se application as seed priming and foliar spray than canola for both years. It has concluded that Se application (either foliar or priming) can potentially alleviate adverse effects of drought stress in camelina and canola by eliciting various physio-biochemicals attributes under drought stress. Furthermore, Se application was also helpful for crop health under irrigated condition.     

Is PF-00835231 a Pan-SARS-CoV-2 Mpro Inhibitor? A Comparative Study

The COVID-19 outbreak continues to spread worldwide at a rapid rate. Currently, the absence of any effective antiviral treatment is the major concern for the global population. The reports of the occurrence of various point mutations within the important therapeutic target protein of SARS-CoV-2 has elevated the problem. The SARS-CoV-2 main protease (Mpro) is a major therapeutic target for new antiviral designs. In this study, the efficacy of PF-00835231 was investigated (a Mpro inhibitor under clinical trials) against the Mpro and their reported mutants. Various in silico approaches were used to investigate and compare the efficacy of PF-00835231 and five drugs previously documented to inhibit the Mpro. Our study shows that PF-00835231 is not only effective against the wild type but demonstrates a high affinity against the studied mutants as well.     

Numerical analysis of dual variable of conductivity in bioconvection flow of Carreau–Yasuda nanofluid containing gyrotactic motile microorganisms over a porous medium

Journal of Thermal Analysis and Calorimetry - The increasing need of the modern era of technology for better ways to increase the heat transfer performance of thermal systems has made nanoliquids...     

Synthesis,Antibacterial, and Antioxidant Evaluation of Novel Series of Condensed Thiazoloquinazoline with Pyrido,Pyrano, and Benzol Moieties as Five- and Six-Membered Heterocycle Derivatives

A novel synthesis of thiazolo[2,3-b]quinazolines 4(a–e), pyrido[2′,3′:4,5]thiazolo[2,3-b]quinazolines {5(a–e), 6(a–e), and 7(a–e)}, pyrano[2′,3′:4,5]thiazolo[2,3-b]quinazolines 8(a–e), and benzo[4,5]thiazolo[2,3-b]quinazoloine9(a–e) derivatives starting from 2-(Bis-methylsulfanyl-methylene)-5,5-dimethyl-cyclohexane-1,3-dione 2 as efficient α,α dioxoketen dithioacetal is reported and the synthetic approaches of these types of compounds will provide an innovative molecular framework to the designing of new active heterocyclic compounds. In our study, we also present optimization of the synthetic method along with a biological evaluation of these newly synthesized compounds as antioxidants and antibacterial agents against the bacterial strains, like S. aureus, E. coli, and P. aeruginosa. Among all the evaluated compounds, it was found that some showed significant antioxidant activity at 10 μg/mL while the others exhibited better antibacterial activity at 100 μg/mL. The results of this study showed that compound 6(c) possessed remarkable antibacterial activity, whereas compound 9(c) exhibited the highest efficacy as an antioxidant. The structures of the new synthetic compounds were elucidated by elemental analysis, IR, ¹H-NMR, and ¹³C-NMR.     

Host-guest molecular encapsulation of cucurbit[7]uril with dillapiole congeners using docking simulation and density functional theory approaches

Structural Chemistry - Binding affinity and intermolecular interactions are essential characteristics that could be used to comprehend molecular recognition between molecules in supramolecular...     

Synthesis and cytotoxic evaluation of novel brominated N-alkyl pyrano[3,2-c]quinolinones

A novel series of 6-alkyl-4-bromopyrano[3,2-c]quinoline-2,5-diones ( 2a–c ), 6-alkyl-3,4-dibromopyrano[3,2-c]quinoline-2,5-diones ( 4a–c ), and 6-alkyl-3-amino-bromopyrano[3,2-c]quinoline-2,5-diones ( 6a–c ) were synthesized via appropriate conventional methods and in good yields. The structures of target compounds were approved by elemental analysis, IR, ¹H NMR, ¹³C NMR, and mass spectrometry. The antitumor inhibitory activities of the new compounds were evaluated on several cancer cell lines, A-549 (human lung cancer), HCT-116 (human colon cancer), MCF-7 (breast cancer), and HePG-2 (human liver cancer). Moreover, 50% inhibitory concentrations, IC₅₀, were established. 5-Fluorouracil was used as a positive control in the viability assay. The screening results showed that most of the examined compounds exposed powerful inhibition activity toward various cell lines. Particularly, Compound 4c exhibited higher cytotoxic activity against four tumor cell lines than the reference drug, 5-fluorouracil, with significantly lower IC₅₀ values. Accordingly, most of the synthesized compounds would be a better prospective growth in the anticancer drug discovery.     

Synthesis of Fe3O4-supported Schiff base Cu (II) complex: a novel efficient and recyclable magnetic nanocatalyst for one-pot three-component synthesis of quinolin-5-one,chromene-3-carbonitrile and phthalazine-5,10-dione derivatives

Research on Chemical Intermediates - In this research, synthesis and characterization of a novel Schiff base Cu (II) complex immobilized on Fe3O4@SiO2 nanoparticles are reported. Then, the...