A selective method for the qualitative determination of paroxetine in forensic biological samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Paroxetine is a schedule H antidepressant drug. It has occasionally been implicated in lethal overdoses. To identify and estimate the level of this drug in toxicological samples is a forensic challenge. Attempts have been made in the past to extract and detect paroxetine in blood samples by using a variety of techniques such as gas chromatography, gas chromatography-mass spectrometry, high pressure liquid chromatography, liquid chromatography-mass spectrometry, etc. However, no studies have been reported in other biological samples. In this study, an attempt has been made to identify paroxetine in biological samples by liquid chromatography-tandem mass spectrometry in multiple reaction monitoring mode at 330.15192.11. The product ion spectra proved to be very helpful in identification of the drug. Furthermore, multiple reaction monitoring (MRM) enhances the reliability and specificity of the method. The use of modified mobile phase produces good quality of qualifier ions. This method appears to be simple, sensitive, specific, and reliable.

Adsorption studies on wastewaters from cypermethrin manufacturing process using activated coconut shell carbon.

Cypermethrin is a pyrethroid pesticide and is used in the control of a wide range of insects on crops like vegetables, cereals, maize etc. In the present study, the adsorption efficiency of coconut shell based activated carbon for the removal of color and organic matter from cypermethrin pesticide manufacturing industrial wastewater was investigated. Effect of carbon dosage, pH and contact time on the removal of COD was also studied. Equilibrium and kinetic studies were carried out and the data was fitted in Freundlich and Langmuir models. The study proved that activated coconut shell carbon (acc) is an efficient adsorbent for treatment of cypermethrin industrial wastewaters under study.

Development of spray reagent for TLC detection of pyrethroid insecticides using picric acid.

There have been a variety of approaches developed since the 1970s to detect pyrethroid pesticides based on gas chromatography (GC), thin layer chromatography (TLC), and high performance liquid chromatography (HPLC) with ultraviolet detection. A new thin layer chromatographic method was developed for the detection of common pyrethroids in forensic toxicology case exhibits. Various solvent systems were tried as mobile phase with different spray reagents; picric acid was used as specific spray reagent for deltamethrin, fenvalerate, and cypermethrin. The method developed is rapid and sensitive and can be used for routine case analysis with better separation. A new modified spray reagent was developed for the detection of synthetic pyrethroids containing a hydrolysable nitrile group such as deltamethrin, fenvalerate and cypermethrin using picric acid, that produces reddish-orange spots on a yellow background.

Monitoring of fluoride concentration in ground water of Prakasham District in India: correlation with physico-chemical parameters.

Fluoride concentrations in surface and ground water samples were determined in eight villages of Prakasham district in India. Thirty-eight samples were collected and analysed for fluoride content along with pH, electrical conductivity, total dissolved solids (TDS), total hardness, total alkalinity, chlorides (C1), sulfates (SO2-) and nitrates (NO ). Fluoride concentrations in surface and ground water samples of these villages varied between 0.5 and 9.0 mg/L. Groundwater samples contained high concentrations of fluorides compared to open well and pond water samples, which could be a major source of fluoride in water since the geological formation of this area consists of fluorite and fluoropatite. From the data, it is evident that the population in the study area is severely affected by fluorosis. Dental and skeletal fluorosis and deformation of bones in children as well as adults were observed in the study area indicating the consequences of excess fluoride concentration. Fluoride concentrations showed good correlation with TDS concentrations (R2 of 0.61) compared to other physico-chemical parameters [EC (R2 - 0.36), nitrate (R - 0.24), total hardness (R - 0.12), chloride (R2 - 0.06) and sulfate (R2 - 4 x 10(-6))].

Fe(II) speciation and its uptake by free and immobilized cells of Pseudomonas fluorescens from industrial waste water.

Studies are carried out to remove Fe(II) from wastewater using free and immobilized cells of Pseudomonas fluorescens. Experiments are carried out with free cells between 6 and 8 pH and the uptake of Fe(II) is observed to be maximum at pH 7. Further experiments are done at pH 7. Studies with free and immobilized cells revealed that immobilized cells are more efficient for the removal of Fe(II) than free cells. Fe(II) uptake with Pseudomonas fluorescens is also investigated after the addition of NaCl and MgCl2 to the cells. It is found that the uptake has increased when Sodium chloride (NaCl) and Magnesium Chloride (MgCl2) mixed cells are used. Effect of deficiency of nutrients is also studied. It is found that glucose deficient conditions inhibit Fe(II) uptake more than yeast extract deficient ones. pH also plays an important role in the transport of Fe(II) across the membrane of the cells.

Antifeedant activity of some new heterocyclic compounds against the larvae of Spodoptera litura F.

The antifeedant activity of diisoflavones a synthetic products is reported for the first time against S. litura. The antifeedant activity was tested employing the non-choice test method against the 4th instar pre-starved larvae.