Preparation of chitosan grafted graphite composite for sensitive detection of dopamine in biological samples

© 2016 Elsevier Ltd. All rights reserved.The accurate detection of dopamine (DA) levels in biological samples such as human serum and urine are essential indicators in medical diagnostics. In this work, we describe the preparation of chitosan (CS) biopolymer grafted graphite (GR) composite for the sensitive and lower potential detection of DA in its sub micromolar levels. The composite modified electrode has been used for the detection of DA in biological samples such as human serum and urine. The GR-CS composite modified electrode shows an enhanced oxidation peak current response and low oxidation potential for the detection of DA than that of electrodes modified with bare, GR and CS discretely. Under optimum conditions, the fabricated GR-CS composite modified electrode shows the DPV response of DA in the linear response ranging from 0.03 to 20.06 μM. The detection limit and sensitivity of the sensor were estimated as 0.0045 μM and 6.06 μA μM-1 cm-2, respectively

Ontogenesis, distribution and relative sensitivity of hCG receptors to hCG and LH in goat ovaries

The binding of [<SUP>125</SUP>I] hCG to immature and mature follicles and corpora lutea of goat ovaries has been studied. The hormone is bound maximally by corpora lutea although mature follicles also exhibit some binding. Immature follicles are practically devoid of receptors for this hormone. In the corpus luteum, the receptors for the hormone are present in thecal and luteal cells. Autoradiographic studies show the location of the bound radioactivity grains primarily along the plasma membranes of these cells, although some radioactivity grains were also seen in the cytoplasm of luteal but not thecal cells. On a mole to mole basis, hCG was found to displace [<SUP>125</SUP>I] hCG from binding to receptors on corpus luteum better than hLH and oLH

Simulation and Design of SRF based Control Algorithm for Three Phase Shunt Active Power Filter

Abstract — Active power filters are effective in mitigating line current harmonics and compensating for the reactive power in the line. There are basically two types of Active Power Filters (APFs): shunt type and series type. Shunt active power filters (SAPFs) represent the most important and most widely used filters in industrial purposes, this is due not only to the fact that eliminate the harmonic current but also they are suitable for a wide range of power ratings. In this paper, Synchronous Reference Frame (SRF) theory is employed to calculate compensating currents while the three phase source is feeding a highly non-linear load. The main objective is to study and investigate the performance of Shunt active power filter using SRF theory. The algorithm is simulated under MATLAB 7.8 environment using Simulinkand SimPowerSystems toolbox. The results shown are within the IEEE Standard 512-1992