Search

Direct methanol fuel cells (DMFCs) offers promising possibilities in meeting future energy needs in a most sustainable way. To electro oxidize methanol at anode of DMFCs, till date Pt and Pt-based materials were widely employed. To improve the utilization of precious metals it is highly desirable to disperse them on conductive carbon structures. Here, we synthesized ultra-range bimetallic platinum–palladium (Pt–Pd) nanospheres (NSs) with uniform dispersion on reduced graphene oxide (RGO) sheets by a simple hydrothermal method and studied their efficacies towards methanol oxidation reaction (MOR). From HR-TEM analysis, it was found that the synthesized bimetallic Pt–Pd NSs possess an average particles size of about 5 to 7 nm consistent with XRD data. The MOR electro catalytic activity of bimetallic PtPd-RGO NSs was higher compared to homemade mono metallic Pt-RGO, Pd-RGO catalysts and commercial E-tekPt/C.

Flavonoids do have a lot of pharmacologic effects and health benefits. And are a group of polyphenolic compounds. For the effective delivery of flavonoids, to improve the bioavailability they are being formulated in many ways and for this an accurate analysis in a formulation, a suitable analytical method is needed. For the analysis of flavonoids, High-Performance Liquid Chromatography offers an accurate, sensitive technique. Hence in the present work, an attempt is made to develop and validate an economic, rapid and sensitive method for quantitative determination of Hesperidin in solid lipid nanoparticles based on isocratic reversed phase high-performance liquid chromatography. Chromatography was performed on a C-8 reverse-phase analytical column and photo diode array detector, the following conditions were chosen as optimal: mobile phase – Mobile phase A (methanol : acetonitrile – 60:40) 15% v/v: Mobile phase B (purified water acidified with 0.20 % ortho-Phosphoric acid-pH 2.5) 85% v/v, flow rate – 1.0 mL/min and ambient temperature. Linearity was observed in the concentration range 1-25 µg /mL with a correlation coefficient of 0.999 and the limit of detection (LOD) is 0.25µg/mL and limit of quantification (LOQ) is 0.81µg/mL. The proposed method allowed direct determination of Hesperidin with a high degree of accuracy, precision, robustness, specificity in solid lipid nanoparticles in the presence of formulation excipients. Keywords: Hesperidin, Solid Lipid Nanoparticle Formulation, Quantitative Analysis, Isocratic Reverse Phase High-Performance Liquid Chromatography

This research is focused on the rational approach to design and synthesis of a novel series of triazole linked pyrrole derivatives through a sequential Paal–Knorr reaction and Click chemistry. These new molecules were screened against Mycobacterium tuberculosis H37Rv and found to display promising anti-mycobacterial activity. Among various compounds, 7g and 7l were identified as leads with minimum inhibitory concentration value 0.78 (μg/mL), which are more effective than standard drugs such as pyrazinamide, ethambutol, and ciprofloxacin and less active than isoniazid and rifampicin. These molecules (minimum inhibitory concentration values

A three-component, four center Ugi reaction of 3-(1-(2-aminophenyl)-5-phenyl-1H-pyrrol-2-yl)propanoic acid with aromatic aldehyde and t-butyl isocyanide has been achieved to produce a novel class of N-tert-butyl-2-(6-oxo-11-phenyl-7,8-dihydrobenzo[b]pyrrolo[1,2-d][1,4]diazacine-5(6H)-yl)-2-phenylacetamides in moderate to good yields.

A chromophoric reagent, 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC), was employed for the sensitive spectrophotometric determination of gold(III). The gold(III) ion forms a blue-coloured complex with HMBATSC in an aqueous dimethyl formamide at pH 6.0. The gold complex shows the absorption maximum at 385 nm, and Beer's law was obeyed in the range 0.49–8.37 μg mL−1. The molar absorptivity and Sandell's sensitivity were found to be L mol−1 cm−1 and 0.015 μg cm−2, respectively. The complex shows 1 : 1 [Au(III) : HMBATSC] stoichiometry with a stability constant of . The interference effect of various diverse ions has been studied. In addition to zero-order, first- and second-order derivative spectrophotometric methods were also developed for the determination of gold(III) in microgram amounts which were more sensitive than the zero-order method. The developed method has been used for the determination of gold(III) in environmental water samples and certified reference materials. The results were in excellent agreement with the certified values.

2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) has been synthesized, characterized and employed as a simple simultaneous second order derivative spectrophotometric method for the analysis of a three-component system containing cobalt(II) nickel(II) and vanadium(V) without separation. The reagent (HMBATSC) reacts with cobalt(II), nickel(II) and vanadium(V) at pH 6.0, forming soluble brown, yellow and green coloured species, respectively. Cobalt, nickel and vanadium present in the mixture are simultaneously determined without solving the simultaneous equations by measuring the second derivative amplitudes at 460 nm, 450 nm and 430 nm, respectively. Further, the derivative amplitudes obey Beer's law at 460 nm, 450 nm and 430 nm for Co(II), Ni(II) and V(V) in the range 0.059 – 3.535 μg ml−1, 0.058 – 3.425 μg ml−1 and 0.051 – 4.074 μg ml−1, respectively. A large number of additional ions did not interfere with the method. The simultaneous method can be applied for the determination of cobalt(II) ...

A three-component, four center Ugi reaction of pyrrol derivatives (I) with aromatic aldehydes and t-butyl isocyanide is achieved to produce a novel class of fused heterocycles.