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Arsenic is a toxic element and is found in natural waters throughout the globe. The purpose of present study is to demonstrate the As (V) uptake by orange peel from real ground water samples through adsorption. Different parameters such as pH, shaking speed, contact time, adsorbent dosage, concentration, volume and temperature etc, were optimized. The maximum uptake capacity was observed at pH-7. The sorption was found to be time dependent and the kinetics followed well by the Morrisweber, Pseudo second order and Elovich equations. The Freundlich, Langmuir, Dubinin Redushkevich and FloryHuggins isotherm were used to model the adsorption behavior of arsenic retention. Thermodynamic parameters calculated from these isotherms show that the adsorption was spontaneous and endothermic in nature. Orange peel was found to be effective (*85%) for arsenic removal from real water systems containing concomitant ions.

An analytical method has been developed for the separation of glyoxal (Go), methylglyoxal (MGo), and dimethylglyoxal (DMGo) by MEKC using stilbenediamine (SD) as derivatizing reagent, separation time 6.5 min, SDS as micellar medium at pH 8, and sodium tetraborate (0.1 M) as buffer. Uncoated fused-silica capillary, effective length 50 cm x 75 microm id; applied voltage 20 kV and photodiode array detection, were used. Calibration was linear within 0.02-150 microg/mL with detection limits 3.5-5.8 ng/mL. Go and MGo, observed for diabetic and healthy volunteers, were within 0.098-0.193 microg/mL Go and 0.106-0.245 microg/mL MGo with RSD 1.6-3.5 and 1.7-3.4%, respectively, in diabetics against 0.016-0.046 microg/mL Go and 0.021-0.066 microg/mL MGo with RSDs 1.5-3.5 and 1.4-3.6%, respectively, in healthy volunteers. Go and MGo in diabetics were also measured by standard addition and DMGo as an internal standard. Additives do not contribute significantly to Go and MGo matrix.