University of Madras

About: University of Madras is a education organization based out in Chennai, Tamil Nadu, India. It is known for research contribution in the topics: Ring (chemistry) & Lipid peroxidation. The organization has 8496 authors who have published 11369 publications receiving 211152 citations. The organization is also known as: Madras University & University of Chennai.

Towards green synthesis of monodisperse Cu nanoparticles: An efficient and high sensitive electrochemical nitrite sensor

Abstract: The development of highly stable and biocompatible Cu nanocomposite has been employed herein as an electrocatalytic active material for electrochemical sensing. The synthesis of carboxymethyl cellulose (CMC) stabilized Cu nanoparticles in aqueous medium under room temperature has been carried out. To identify the surface properties of the synthesized Cu nanoparticles, X-ray diffraction (XRD) and X-ray photoelectron spectroscopic (XPS) studies have been carried out. The as-prepared Cu nanoparticles were dispersed with multi-walled carbon nanotubes (MWCNTs) and the resultant dispersion has been deposited over glassy carbon (GC) electrode to obtain Cu/MWCNTs/GC modified electrode. The Cu/MWCNTs modified GC electrode exhibits a well-defined oxidation peak at Epa = 0.93 V (vs. SCE) towards the oxidation of nitrite. Amperometric investigations of the modified electrode revealed a wide linear range for nitrite from 5 μM to 1260 μM with a sensitivity and detection limit of 455.84 μA mM−1 cm−2 and 1.8 μM, respectively. The proposed modified electrode displayed excellent selectivity and reproducibility and has been successfully utilized for determination of nitrite in real samples.

Synthesis of lateral macrobicyclic compartmental ligands: structural, magnetic, electrochemical, and catalytic studies of mono- and binuclear copper(II) complexes.

Abstract: A series of putative mono- and binuclear copper(II) complexes, of general formulas [CuL](ClO4) and [Cu2L](ClO4)2, respectively, have been synthesized from lateral macrocyclic ligands that have different compartments, originated from their corresponding precursor compounds (PC-1, 3,4:9,10-dibenzo-1,12-[N,N‘-bis{(3-formyl-2-hydroxy-5-methyl)benzyl}diaza]-5,8-dioxacyclotetradecane; and PC-2, 3,4:9,10-dibenzo-1,12-[N,N‘-bis{(3-formyl-2-hydroxy-5-methyl)benzyl}diaza]-5,8-dioxacyclopentadecane). The precursor compound PC-1 crystallized in the triclinic system with space group P1. The mononuclear copper(II) complex [CuL1a](ClO4) is crystallized in the monoclinic system with space group P21/c. The binuclear copper(II) complex [Cu2L2c](ClO4)2 is crystallized in the triclinic system with space group P1; the two Cu ions have two different geometries. Electrochemical studies evidenced that one quasi-reversible reduction wave (Epc = −0.78 to −0.87 V) for mononuclear complexes and two quasi-reversible one-electron-tr...

Combined efficacies of lipoic acid and 2,3-dimercaptosuccinic acid against lead-induced lipid peroxidation in rat liver

Abstract: Oxidative stress with subsequent lipid peroxidation has been postulated as one mechanism for lead toxicity. Hence in assessing the protective effects of lipoic acid (LA) and meso 2,3-dimercaptosuccinic acid (DMSA) on lead toxicity, they were tested either separately or in combination for their effects on selected indices of hepatic oxidative stress. Elevated levels of lipid peroxides were accompanied by altered antioxidant defense systems. Lead acetate (Pb - 0.2%) was administered in drinking water for five weeks to induce toxicity. LA (25 mg kg−1 body wt. day−1 i.p) and DMSA (20 mg kg−1 body wt. day−1 i.p) were administered individually and also in combination during the sixth week. Lead damage to the liver was evident in the decreases in hepatic enzymes alanine transaminase (−38%), aspartate transaminase (−42%) and alkaline phosphatase (−43%); increases in lipid peroxidation (+38%); decreases in the antioxidant enzymes catalase (−45%), superoxide dismutase (−40%), glutathione peroxidase (−46%) and decreases in glutathione (−43%) and decreases in glutathione metabolizing enzymes, glutathione reductase (−59%), glucose-6-phosphate dehydrogenase (−27%) and glutathione-S-transferase (−42%). In combination LA and DMSA completely ameliorated the lead induced oxidative damage. Either compound alone was however only partially protective against lead damage.