A new kinetic spectrophotometric method for the determination of major metabolite of heroin in biological samples

This study describes a simple,rapid and selective catalytic kinetic spectrophotometric method for the determination of 6- monoacetylmorphine（6-MAM） as major metabolite of heroin in biological samples.The method is based upon the catalytic effect of 6-MAM on the oxidation of Janus Green by bromate in acid media.The reaction was followed spectrophotometrically by measuring the decrease in absorbance of Janus Green at 618 nm.The dependence of sensitivity on the reaction variables was studied.Under optimum conditions,two linear calibration curves over the range 0.1-1.0μg mL^-1 and 1.0-34.0μg mL^-1 of 6- MAM were obtained.The detection limit was 1.2×10²μg mL^-1 of 6-MAM.The relative standard deviations for six replicate determinations of 0.8 and 5.0μg mL^-1 of 6-MAM were 1.4 and 1.1%respectively.The effect of various species commonly associated with heroin in real samples was also investigated.The proposed method was successfully applied in human urine and serum samples with satisfactory results.     

Curative Effect of Catechin Isolated from Elaeagnus Umbellata Thunb. Berries for Diabetes and Related Complications in Streptozotocin-Induced Diabetic Rats Model

In this study, catechin (CTN) isolated from Elaeagnus umbellata was evaluated for in vitro antioxidant potential and inhibition of carbohydrate digestive enzymes (α-amylase and α-glucosidase). The compound was also tested for its in vivo antidiabetic potential using Sprague-Dawley rats as experimental animals. The effects of various doses of catechin in STZ (Streptozotocin) induced diabetic rats on fasting blood glucose level, body weight, lipid parameters, hepatic enzymes, and renal functions were evaluated using the reported protocols. The CTN exhibited the highest percent antioxidant for free radical scavenging activity against DPPH and ABTS free radicals, and inhibited the activity of carbohydrate digestive enzymes (with percent inhibition values: 79 ± 1.5% α-amylase and 80 ± 1.1% α-glucosidase). Administration CTN and standard glibenclamide significantly decreased the fasting blood glucose level and increased the body weight in STZ-induced diabetic rats. CTN significantly decreased the different lipid parameters, hepatic, and renal function enzyme levels along with Hb1c level in diabetic rats, while significantly increasing the high-density lipoprotein (HDL) level with values comparable to the standard glibenclamide. Further, the altered levels of glutathione and lipid peroxides of liver and kidney tissues were restored (by CTN) to levels similar to the control group. CTN significantly increased the antioxidant enzyme activities, total content of reduced glutathione, and reduced the malondialdehyde (MDA) level in rat liver and kidney tissues homogenates, and also corrected the histopathological abnormalities, suggesting its antioxidant potential.     

4E analysis and tri-objective optimization of a triple-pressure combined cycle power plant with combustion chamber steam injection to control NOx emission

This article presents a novel triple-pressure combined cycle power plant (CCPP) with a heat recovery steam generator (HRSG) configured with heat exchangers of multiple pressure levels, same as the real case. In addition, combustion chamber steam injection is added to the top cycle in order to reduce hazardous emissions. The research investigates energy, exergy, economic, and environmental aspects of the system to initiate sustainable development in said areas. A thorough parametric study is carried out to evaluate the effects of steam injection and other decision variable on emissions and system performance. Then, the total cost rate and the CO₂ index are minimized while maximizing the second law efficiency via a tri-objective optimization using the genetic algorithm. The outcome of the economic analysis is that the HRSG has the maximum total cost rate among all the components, namely 0.1673 $/s. The environmental impact  assessments indicate that the CO₂ and NO emission has considerable molar fractions of 0.035 and 6.88?×?10^?4, respectively. As a result of the tri-objective optimization, a 3D Pareto Frontier is presented, which pointed out the maximum attainable exergy efficiency is 50.32%, as well as the minimum total cost rates of 8.04 $/s and CO₂ index of 0.34 kg/kWh. Finally, the scatter distribution of major decision variables revealed the optimum range of decision variables in which the optimum points of the Pareto Frontier are obtained. Accordingly, the scatter distribution showed that 46 kg s^?1 is the optimum value for steam injection flow rate in terms of efficiency, cost and emission optimization.

     

Narrow bandgap semiconducting polymers for solar cells with near-infrared photo response and low energy loss

The alternating diketopyrrolopyrrole (DPP)-Quinoxaline (Qx) based conjugated polymers are synthesized and investigated as electron donors for polymer solar cells (PSCs). Through the substitution of phenyl in Qx unit at para (p) and meta (m) positions with methoxy group, the resultant DPP-pMQx and DPP-mMQx polymers possess narrow optical band gap (1.32 and 1.26 eV) with relatively low-lying highest occupied molecular orbitals. The obtained photovoltaic devices indicate that the combination of DPP with weak acceptor Qx is helpful to develop narrow bandgap polymers with near-infrared photo response and low energy loss (0.58 eV for DPP-mMQx) in PSC devices.     

Simultaneous determination of methotrexate and metoclopramide in physiological fluids using RP-HPLC with ultra-violet detection; application in evaluation of polymeric nanoparticles

Methotrexate (MTX) is an anticancer drug while metoclopramide (MCP) is an antiemetic agent. Both the drugs are commonly coprescribed to avoid the emesis caused by anticancer drug. In this study, a novel, rapid, sensitive, and cost-effective reverse-phase high-performance liquid chromatography method was developed and validated for simultaneous determination of the methotrexate and metoclopramide in biological and pharmaceutical samples using sparfloxacin as internal standard. The analytes were separated on a Kromasil 100-5C18 RP (250?×?4.6?mm, 5?µm) column, methanol, and 0.05% trifloroacetic acid (36:64?v/v) as mobile phase with a flow rate of 1?mL/min, detection wavelength of 290?nm, and column oven temperature at 40°C. Both the analytes were extracted from physiological fluids (bovine aqueous humor, vitreous humor, and human plasma) using mixture of methanol and 10% perchloric acid (50:50 v/v). The method was linear over the concentration range of 0.025–1.0?µg/mL for methotrexate and 0.030–1.0?µg/mL for metoclopramide. The % recovery from human plasma was 98.57 and 96.74% for MTX and MCP, respectively, while from aqueous humor and vitreous humor was 95.84 and 98.51% for MTX.

The developed method was applied for in vitro release of MTX from polymeric nanoparticles and can be applied for analysis of pharmaceutical and biological samples containing both the drugs.     

Experimental and theoretical characterization of 3-amino-1-phenyl-2-buten-1-onato ligand and its copper(II) and nickel(II) complexes: synthesis, characterization, X-ray structures, DFT and TDDFT studies

This article presents a combined experimental and computational investigation of 3-amino-1-phenyl-2-buten-1-onato, APBO ligand and its copper(II) and nickel(II) complexes. APBO is an unsymmetrical, bidentate and monoanionic ligand with different coordinating atoms (N,O). A comparison among different possible conformers of the ligand has been carried out using density functional theory (DFT) method at the B3LYP/6-31+G(d,p) level. It was demonstrated that two factors control stability of the compounds as hydrogen bonding (conventional and nonconventional) and resonance effect. The effectiveness of each of these parameters on the stability of ligands is discussed. The prepared homoleptic complexes of [Ni(APBO)₂] and [Cu(APBO)₂] were characterized with IR, NMR, UV–Vis spectroscopic techniques. The X-ray crystallography of [Ni(APBO)₂] demonstrated that the bidentate APBO binds to the metal center in trans fashion and the geometry around the nickel atom is square planar. The experimental studies on the complexes were accompanied computationally by the DFT and time-dependent DFT calculations.     

Novel Conductive PANI/Hydrophilic Thiacalix[4]areneNanocomposites: Synthesis,Characterization andInvestigation of Properties简

Nanocomposites of polyaniline(PANI) and the macrocycle thiacalix[4]arene tetra sulfonate(TCAS) were successfully synthesized in feed ratios of 1:0.25, 1:0.50 and 1:0.75 by three prevail synthetic methods, i.e. in situ polymerization, emulsion polymerization and solution casting technique. The structures of the nanocomposites were confirmed by FTIR, UV-Vis, XRD, SEM, and TEM techniques. The conductivity was measured by a four probe method. The conductivity was recorded to be as high as 105 × 10 2S cm 1for the nanocomposite with a nanometer size structure and homogeneously distributed morphology. The electroactivity of the nanocomposites was approved by cyclic voltammetry(CV) and impedance spectroscopy technique(EIS). The antioxidant ability and thermal property of the composites were further studied. Preliminary studies have evidenced the production of conductive nanocomposites with good thermal property and relatively good solubility in N-methyl 2-pyrrolidone(NMP), with the antioxidant activity reaching up to 80%.     

Hydrogen Adsorption Study upon Ni/AI203 Nano-composite Synthesized by MOCVD Technique

The hydrogen adsorption （storage） studies upon Ni/A1203 nano-composite prepared by metal organic chemical vapor deposition technique （MOCVD） exploiting single source molec ular precursor （SSP） approach were carried out. The Ni/A1203 nano-composite is prepared in cold walled MOCVD reactor by the decomposition of SSP, [H2AI（OtBu）]2, on a substrate holding Ni（acac）2 powder. The SSP is a reducing agent which reduces Ni＋2 to Ni0 and works as source for Al203 matrix in which the Ni0 is dispersed. The resulting Ni/A1203 nano-composite is characterized by XRD, SEM, TEM, and EDX. The hydrogen adsorption （storage） studies are performed using home-made Sievert＇s type apparatus. The hydrogen storage studies reveal that approximately 2.9% （mass ratio） hydrogen can be stored in the Ni/A1203 nano-composite. The results show that Ni/A1203 nano-composite can be a po- tential candidate for hydrogen storage which can be used for onboard fuel purposes.