Cr(VI)-induced DNA damage is lessened by the modulation of hsp70 via increased GSH de novo synthesis in Drosophila melanogaster.

Hexavalent chromium [Cr(VI)] is a genotoxic chemical, and in the chemical-exposed organism, oxidative stress is one of the leading causative mechanisms of genotoxicity. Heat shock protein-70 (Hsp70) is reported to be modulated in environmental chemical exposed organisms. Inadequate information on the protective role of Hsp70 in chemical-induced DNA lesions prompted us to investigate this possibility in a well-studied genetically tractable in vivo model Drosophila melanogaster. In the midgut cells of Cr(VI)-exposed hsp70-knockout (KO), -knockdown (KD), and -overexpression Drosophila strains, no significant change in double-strand breaks generation was observed in comparison to similarly exposed w 1118 and the respective genetic control strain after 48 h. Therefore, the role of hsp70 was investigated on oxidative DNA damage induction in the exposed organisms after 24 h. Oxidized DNA lesions (particularly oxidized purine-based lesions), 8-oxo-dG level, and oxidative stress endpoints were found to be significantly elevated in hsp70-KO and -KD strains in comparison to similarly exposed w 1118 and respective genetic control strain. On the contrary, in ubiquitous hsp70-overexpression strain exposed to Cr(VI), these endpoints were significantly lowered concurrently with increased GSH level through elevated gclc, and gclm expression, Gclc level, and GCL activity. The study suggests that as a consequence of hsp70 overexpression, the augmented GSH level in cells vis-a-vis GSH de novo synthesis can counteract Cr(VI)-induced oxidized DNA lesions.

Identification of markers of depression and neurotoxicity in pesticide exposed agriculture workers.

Earlier, we reported that chronic exposure to pesticides causes a reduction in the acetylcholinesterase activity and hematological and biochemical alterations in agriculture workers. In continuation with that, the present study aimed to investigate the pesticide-induced neurochemical imbalance and its association with behavior alterations in agricultural workers. A significant increase in depressive symptoms, assessed by the Beck Depression Inventory-II was observed in pesticide exposed workers as compared to the unexposed. A decrease in the level of dopamine in plasma and levels of dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acids, norepinephrine, serotonin, and hydroxyindoleacetic acid in urine was also observed. An increase in the levels of MAO-A and MAO-B has also been observed in these individuals. The decreased levels of neurotransmitters in the blood and urine have been linked with increased levels of MAO and pesticide residues in plasma and urine. Furthermore, these changes were associated with a higher incidence of depression in agricultural workers.

Overexpression of cerebral cytochrome P450s in prenatally exposed offspring modify the toxicity of lindane in rechallenged offspring.

Prenatal exposure to low doses of lindane, an organochlorine insecticide used in public health and agriculture, induced a persistent increase in the expression of cerebral cytochrome P450s (CYPs) in rat offspring and modify the adult response to a later exposure of xenobiotics. To understand the mechanism involved in the modification of adult response, rat offspring exposed prenatally to lindane (p.o.; 0.25 mg/kg b.wt. from gestation day 5-21) were rechallenged with lindane (p.o.; 5 mg/kg X 5 days) postnatally at 9- or 18- or 27 weeks. The greater magnitude of increase in the expression of cerebral CYPs in rechallenged offspring and decline in the magnitude of increase in CYPs with increasing age correlated with the amount of lindane accumulating in the brain. Significant alterations in the circulatory levels of hormones in the rechallenged offspring suggest that these alterations may partly account for the persistence in the increase in the cerebral CYPs during development. Epigenetic data further revealed alterations in histone H3 acetylation and DNA methylation in promoter regions of cerebral CYPs isolated from rechallenged offspring at 9- or 18- or 27 weeks. Bisulphite sequencing revealing critical CpG methylation changes in the promoter regions in rechallenged offspring at 9 weeks demonstrated imprinting of the cerebral CYPs. Further, a greater magnitude of increase in apoptosis in the brain of rechallenged offspring has suggested that enhanced responsiveness of cerebral CYPs, which may result due to alterations in circulatory hormones, increased accumulation of lindane in the brain and epigenetic regulation of CYPs, is of toxicological relevance.

Transformation of Santonin to a Naproxen Analogue with Anti-Inflammatory Activity.

Santonin, a natural product, was aromatized with molecular iodine as the catalyst. The new compound was characterized as ( S)-methyl-2-(7-hydroxy-5,8-dimethylnaphthalen-2-yl) propanoate (2) based on 2D NMR spectroscopic data. Structurally, compound 2 was highly similar to the anti-inflammatory drug naproxen. The new naproxen analogue had significant potency against cyclooxygenase 1 and 2 (IC50 = 31.0 and 66.1 µM, respectively).

Vortex-assisted surfactant-enhanced emulsification microextraction combined with LC-MS/MS for the determination of glucocorticoids in water with the aid of experimental design.

An efficient and inexpensive method using vortex-assisted surfactant-enhanced emulsification microextraction (VASEME) based on solidification of floating organic droplet coupled with ultraperformance liquid chromatography-tandem mass spectrometry is proposed for the analysis of glucocorticoids in water samples (river water and hospital wastewater). VASEME was optimized by the experimental validation of Plackett-Burman design and central composite design, which has been co-related to experimental design. Plackett-Burman design showed that factors such as vortex time, surfactant concentration, and pH significantly affect the extraction efficiency of the method. Method validation was characterized by an acceptable calibration range of 1-1000 ng L-1, and the limit of detection was in the range from 2.20 to 8.12 ng L-1 for glucocorticoids. The proposed method was applied to determine glucocorticoids in river water and hospital wastewater in Lucknow, India. It is reliable and rapid and has potential application for analysis of glucocorticoids in environmental aqueous samples. Graphical Abstract Low density based extraction of gluococorticoids by using design of experiment.

Whirling agitated single drop microextraction technique for the simultaneous analysis of Paraquat and Maneb in tissue samples of treated mice.

A new microextraction technique, whirling agitated single drop microextraction, has been proposed for the simultaneous analysis of Paraquat and Maneb in tissue samples before liquid chromatography with tandem mass spectrometry. This technique is based on the idea that the escalatory motion of the sample solution along with the extraction solvent increases the movement of molecules into the extraction solvent. In this technique, a simple handheld rotator was utilized to rapidly agitate the biphasic extraction system for the instantaneous extraction of targeted analytes. After extraction, the extracted phase was directly solidified by cooling in crushed ice and easily collected using a micro-spatula. The method showed good performance by achieving sensitive detection limits at 4.81 ng g(-1) (Paraquat) and 9.12 ng g(-1) (Maneb). Mean recoveries and enrichment factors were obtained >91.21% and up to 114 that ensured the preconcentration capacity of the method. The method precision was verified by evaluating intraday variation (n = 10) ≤4.57 (Paraquat) and ≤4.68 (Maneb) in terms of percent relative standard deviation. Additionally, method efficacy was assured by obtaining very little matrix interferences (≤3.11%). Moreover, the method suitability was also checked with its application on tissue samples of intraperitoneally treated mice with Paraquat and Maneb.

Efficient removal of cationic dyes using lemon peel-chitosan hydrogel composite: RSM-CCD optimization and adsorption studies.

The most prominent and easily identifiable factor of water purity is its colour, which may be both physically undesirable, and act as an alert towards potential environmental contamination. The current study describes the optimum synthesis technique for Lemon Peel-Chitosan hydrogel using the Response Surface Methodology integrated Central composite Design (RSM-CCD). This adsorbent is both environmentally friendly and cost-effective. The hydrogel exhibited a maximal dye removal capacity of 24.984, 24.788, 24.862, 23.483, 24.409, and 24.726 mg g-1, for 10 mg L-1 aqueous medium of Safranin O, Methylene blue, Basic fuchsin, Toluidine blue, Brilliant green and Crystal violet, respectively. The adsorption kinetics and isotherm data suggest that the Pseudo second-order kinetic and Freundlich adsorption isotherm models precisely represent the respective behaviour of all the dyes. The thermodynamic viability of the process is determined by the values of ΔG, ΔH, and ΔS. The probable mechanism of adsorption was the electrostatic interaction between the dye molecules and the hydrogel. The regenerated hydrogel had removal efficiencies of over 80 % even after enduring six cycles. Hence, the exceptional recyclability and utility of the adsorbent show their sustainability for wastewater treatment in textile factories.

Oral Release Kinetics, Biodistribution, and Excretion of Dopants from Barium-Containing Bioactive Glass in Rats.

Background: Inorganic biomaterials are biologically active and are used as implants and drug delivery system. They have therapeutically active elements present in their framework that are released in the physiological milieu. Release of these dopants above the supraphysiological limit may produce adverse effects and physicochemical interactions with the loaded drugs. Therefore, this necessitates evaluating the in vivo release kinetics, biodistribution, and excretion profiles of dopants from barium-doped bioglass (BaBG) that has potential anti-inflammatory, antiulcer, and regenerative properties. Methods: In vitro leaching of Ca, Si, and Ba from BaBG was analyzed in simulated body fluid. Release kinetics post single-dose oral administration (1, 5, and 10 mg/kg) was performed in rats. Blood was collected at different time points, and pharmacokinetic parameters of released elements were calculated. The routes of excretion and biodistribution in major organs were evaluated using ICP-MS. Results: Elements were released after the oral administration of BaBG into the plasma. They showed dose-dependent release kinetics and mean residence time. Cmax was observed at 24 h for all elements, followed by a downhill fall. There was also a dose-dependent increase in the volume of distribution, and the clearance of dopants was mostly through feces. Ba and Si were biodistributed significantly in the liver, spleen, and kidneys. However, by the end of day 7, there was a leveling-off effect observed for all elements. Conclusion: All of the dopants exhibited a dose-dependent increase in release kinetics and biodistribution in vital organs. This study will help in dose optimization and understanding of various physicochemical and pharmacokinetic interactions when BaBG is used for future pharmacological studies.

A Study of Dopaminergic Pathway in Neurologic Wilson Disease with Movement Disorder.

Movement disorder (MD) is an important manifestation of neurologic Wilson disease (NWD), but there is a paucity of information on dopaminergic pathways. We evaluate dopamine and its receptors in patients with NWD and correlate the changes with MD and MRI changes. Twenty patients with NWD having MD were included. The severity of dystonia was assessed using BFM (Burke-Fahn-Marsden) score. The neurological severity of NWD was categorized as grades I to III based on the sum score of 5 neurological signs and activity of daily living. Dopamine concentration in plasma and CSF was measured using liquid chromatography-mass spectrometry, and D1 and D2 receptor expression at mRNA by reverse transcriptase polymerase chain reaction in patients and 20 matched controls. The median age of the patients was 15 years and 7 (35%) were females. Eighteen (90%) patients had dystonia and 2 (10%) had chorea. The CSF dopamine concentration (0.08 ± 0.02 vs 0.09 ± 0.017 pg/ml; p = 0.42) in the patients and controls was comparable, but D2 receptor expression was reduced in the patients (0.41 ± 0.13 vs 1.39 ± 1.04; p = 0.01). Plasma dopamine level correlated with BFM score (r = 0.592, p < 0.01) and D2 receptor expression with the severity of chorea (r = 0.447, p < 0.05). The neurological severity of WD correlated with plasma dopamine concentration (p = 0.006). Dopamine and its receptors were not related to MRI changes. The central nervous system dopaminergic pathway is not enhanced in NWD, which may be due to structural damage to the corpus striatum and/or substantia nigra.

Assessing the half-life and degradation kinetics of aliphatic and aromatic hydrocarbons by bacteria isolated from crude oil contaminated soil.

Pollution from the oil industries and refineries has worsened various environmental compartments. In this study, indigenous oil degrading bacteria were isolated from crude oil obtained from an Oil and Natural Gas Corporation (ONGC) asset in Ankleshwar, Gujarat, India. Based on 16S rRNA phylogeny, they were identified as Pseudomonas boreopolis IITR108, Microbacterium schleiferi IITR109, Pseudomonas aeruginosa IITR110, and Bacillus velezensis IITR111. The strain IITR108, IITR109, IITR110, and IITR111 showed 80-89% and 71-78% degradation of aliphatic (C8-C40) and aromatic (4-5 ring) hydrocarbons respectively in 45 d when supplemented with 3% (v/v) waste crude oil. When compared to individual bacteria, the consortium degrades 93.2% of aliphatic hydrocarbons and 85.5% of polyaromatic hydrocarbons. It was observed that the total aliphatic and aromatic content of crude oil 394,470 µg/mL and 47,050 µg/mL was reduced up to 9617.75 µg/mL and 4586 µg/mL respectively in 45 d when consortium was employed. The rate kinetics analysis revealed that the biodegradation isotherm followed first order kinetics, with a linear correlation between concentration (hydrocarbons) and time intervals. The half-life of aliphatic (C8-C40) and aromatic hydrocarbons ranged from 200 to 453 h and 459-714 h respectively. All the bacteria efficiently produced catabolic enzymes such as alkane monooxygenase, alcohol dehydrogenase, and lipase during the degradation of crude oil. These findings indicated that the bacterial consortium can be a better candidate for bioremediation and reclamation of aliphatic and aromatics hydrocarbon contaminated sites.

Impact of arsenic on phosphate solubilization, acquisition and poly-phosphate accumulation in endophytic fungus Serendipita indica.

Symbiotic interactions play a crucial role in the phosphate (Pi) nutrient status of the host plant and offer resilience during biotic and abiotic stresses. Despite a competitive behavior of arsenic (AsV) with Pi, Serendipita indica association promotes plant growth by reducing arsenic bioavailability in the rhizosphere. Reduced arsenic availability is due to the adsorption, accumulation, and precipitation of arsenic in the fungus. The present investigation focused on the fitness and performance of Pi acquisition and utilization in S. indica for growth and metabolism under arsenic stress. The fungus accumulates a massive amount of arsenic up to 2459.3 ppm at a tolerable limit of arsenic supply (1 mM) with a bioaccumulation factor (BAF) 32. Arsenic induces Pi transporter expression to stimulate the arsenic acquisition in the fungus. At the same time, Pi accumulation was also enhanced by 112.2 times higher than the control with an increase in poly-P (polyphosphate) content (6.69 times) of the cell. This result suggests arsenic does not hamper poly-P storage in the cell but shows a marked delocalization of stored poly-P from the vacuoles. Furthermore, an enhanced exopolyphosphatase activity and poly-P storage during arsenic stress suggest induction of cellular machinery for the utilization of Pi is required to deal with arsenic toxicity and competition. However, at high arsenic supply (2.5 and 5 mM), 14.55 and 22.07 times reduced Pi utilization, respectively, was observed during the Pi uptake by the fungus. The reduction of Pi uptake reduces the cell growth and biomass due to competition between arsenic and phosphate. The study suggests no negative impact of arsenic on the Pi acquisition, storage, and metabolism in symbiotic fungus, S. indica, under environmental arsenic contamination.

Synthesis of Biomass-Derived Activated Carbons and Their Immobilization on Alginate Gels for the Simultaneous Removal of Cr(VI), Cd(II), Pb(II), As(III), and Hg(II) from Water.

Low-cost alginate gels of activated carbons were prepared, which were derived from the peels of banana and sweet lime. The synthesized carbon was activated and immobilized on alginate, producing its gel. These gels were categorized according to their methods of drying, in which air drying, freeze drying, and supercritical drying led to the formation of xerogels, cryogels, and aerogels, respectively. The gels were used for adsorption of heavy metals from their aqueous solution. The heavy metals that were targeted for removal were Pb(II), Cd(II), Cr(VI), As(III), and Hg(II). Among all the adsorbents, the alginate cryogel of sweet lime-derived activated carbon (SLACC) showed the highest removal percentage of heavy metals, and thus, it was used for batch study. The adsorption of heavy metals by SLACC was checked at different times, pH values, adsorbent doses, temperatures, and adsorbate concentrations. The study revealed that the pseudo-second-order model best described the kinetic study, while the adsorption followed the Freundlich isotherm. SLACC showed maximum adsorption capacities (q cal) of 3.71, 4.22, 20.04, 7.31, and 4.37 mg/g for Cr, Cd, Pb, As, and Hg, respectively, when 20 mg of SLACC was used for the removal of 4 ppm concentration of the targeted heavy metals from their 20 mL solution. Based on the thermodynamic study, it was found that the adsorption was spontaneous and exothermic. Furthermore, the adsorbent was also used on real water samples and showed up to 90% removal efficiency for these targeted heavy metals. SLACC was regenerated with 0.1 M ethylenediaminetetraacetic acid (EDTA) solution and reused for five cycles, in which the percentage removal of heavy metals was more than 50% till the fourth cycle. Furthermore, the leaching study showed that no toxic elements had leached from SLACC into water, making it a safe adsorbent.

Synthesis of an Alginate-Based Fe3O4-MnO2 Xerogel and Its Application for the Concurrent Elimination of Cr(VI) and Cd(II) from Aqueous Solution.

In this study, magnetite-manganese oxide (Fe3O4-MnO2) nanoparticles were synthesized and immobilized on alginate, producing a magnetite-manganese oxide xerogel (mMOX). This eco-friendly xerogel was used as an adsorbent of Cr(VI) and Cd(II). It was mesoporous and thermally stable, as determined by Brunauer-Emmett-Teller and thermogravimetric analysis. A scanning electron microscope coupled with an energy-dispersive X-ray system, Zetasizer, and attenuated total reflectance-Fourier transform infrared were used for characterization of adsorbents. The performance of the mMOX was investigated for the simultaneous adsorption of Cr(VI) and Cd(II) at different temperatures, pH values, contact times, initial concentrations of the adsorbate, and adsorbent doses. The developed xerogel (mMOX) showed high adsorption capacities of 3.86 mg/g for Cr(VI) and 3.95 mg/g for Cd(II) on 120 min of contact time with 5 ppm Cr(VI) and Cd(II) solution. The kinetic data fitted well with the pseudo-second order, while the Freundlich isotherm model was found to be fit for adsorption data. Thermodynamic study revealed the adsorption to be spontaneous and exothermic. The adsorbent showed useful application for real water samples by more than 75% uptake of Cr and Cd with low adsorption of Na, K, and Mg. The regeneration study indicated that the mMOX could be reused up to six cycles with more than 50% removal of Cr(VI) and Cd(II) ions from aqueous solution with minimal leaching of metal ions (Fe, Ca, Na, K, and Mn) into the solution.

Identification of polycyclic aromatic hydrocarbons in unleaded petrol and diesel exhaust emission.

Inhalation of emissions from petrol and diesel exhaust particulates is associated with potentially severe biological effects. In the present study, polycyclic aromatic hydrocarbons (PAHs) were identified from smokes released by the automobile exhaust from petrol and diesel. Intensive sampling of unleaded petrol and diesel exhaust were done by using 800-cm(3) motor car and 3,455-cm(3) vehicle, respectively. The particulate phase of exhaust was collected on Whatman filter paper. Particulate matters were extracted from filter paper by using Soxhlet. PAHs were identified from particulate matter by reverse phase high performance liquid chromatography using C(18) column. A total of 14 PAHs were identified in petrol and 13 in case of diesel sample after comparing to standard samples for PAH estimation. These inhalable PAHs released from diesel and petrol exhaust are known to possess mutagenic and carcinogenic activity, which may present a potential risk for the health of inhabitants.

Occurrence of phthalic acid esters in Gomti River Sediment, India.

Phthalic acid esters (PAEs) are well-known ubiquitous environmental pollutants and used as plasticizers for the manufacturing of plastic products. During this exploratory study, an attempt has been made to determine the concentration and distribution of five prominent PAEs, viz. di-methyl phthalate (DMP), di-ethyl phthalate (DEP), di-butyl phthalate (DBP), di-(2-ethylhexyl) phthalate (DEHP), and di-octyl phthalate (DOP) in the sediment samples of Gomti River collected from 30 different locations. Identification and quantification of PAEs were performed by high-performance liquid chromatography. The mean concentration values of DMP, DEP, DBP, DEHP, and DOP were found as 10.54, 4.57, 10.41, 31.61, and 5.16 microg/kg, respectively. Limit of detection and limit of quantification for each PAE were also calculated and found in the ranges of 0.09-0.55 and 0.28-1.67 microg/kg. DEHP was the most frequently detected PAE (present in 93.3% samples); however, DOP was found only in 36.7% samples.

Distribution, sources and characterization of polycyclic aromatic hydrocarbons in the sediment of the river Gomti, Lucknow, India.

Sediment samples were collected for PAHs analysis (upstream, midstream and downstream) from the bank of the river Gomti in Lucknow city, India during 2005-2007. Total concentration of the PAHs ranged from 0.068 to 3.153 microg/g dry weight. A correlation existed between the sediment organic carbon content (f(OC)) and the total PAHs concentration with a correlation coefficient (r(2)) of 0.788, suggesting that sediment organic carbon content played an important role in controlling the PAHs levels in the sediments. According to observed molecular indices, PAHs contamination in the river Gomti seems to be originated both from the high temperature pyrolytic process as well as from the petrogenic source, indicating a mixed PAH input pattern.

Determination of organochlorine compounds in fish liver by ultrasound-assisted dispersive liquid-liquid microextraction based on solidification of organic droplet coupled with gas chromatography-electron capture detection.

A simple and rapid method for the extraction of organochlorine compounds (OCs) including poly-chlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in fish liver using ultrasound assisted dispersive liquid-liquid microextraction based on the solidification of floating organic droplet (US-DLLME-SFO) was developed. For reducing the complexity of the matrix, the sample was pre-treated prior to microextraction. Factors affecting US-DLLME-SFO were optimized by using statistical design of experiment (DoE). The analysis was carried out by Gas Chromatography (GC) equipped with micro electron capture detector (µ-ECD). The optimized parameters were 4.8 min of ultrasound, 3.0 mL of Milli-Q and 24 µL of 1-undecanol as an extraction solvent as determined by DoE. US-DLLME-SFO was validated in terms of limit of detection, limit of quantification, dynamic linearity range, coefficient of determination (linearity) and extraction recovery in fish liver for OCs, and the respective values were (1.06-3.84 ng g-1), (3.50-12.67 ng g-1), (1.0-500 ng g-1), (R2 = 0.994-0.999), (88.5-108.4%). Interday and intraday precisions were evaluated as relative standard deviation (% RSD) and the values were ≤10%.

Ionic liquid based ultrasound assisted dispersive liquid-liquid micro-extraction for simultaneous determination of 15 neurotransmitters in rat brain, plasma and cell samples.

Neurotransmitters are signaling molecules which play a key role in the central nervous system allowing signal transmission in the neuronal synapses. The role of these compounds is very crucial in the biological systems. A rapid, sensitive, economical and derivatisation free method has been developed for the analysis of 15 neurotransmitters in a single run on liquid chromatography tandem mass spectrometry. These 15 neurotransmitters are categorized into 5 groups on the basis of their fragmentation pattern. The proposed method "ionic liquid based ultrasound assisted dispersive liquid-liquid microextraction" hyphenated with tandem mass spectrometry is the first report for the analysis of neurotransmitters in cell samples along with other two matrices (rat brain and plasma). All the parameters that influence the extraction efficiency are optimized with aid of response surface methodology and desirability profile. Under these optimized conditions the developed method has been validated. The limit of detection was in the range of (1) 0.021-0.912 µg L-1 for rat brain samples, (2) 0.028-0.978 µg L-1 for plasma samples and (3) 0.025-0.945 µg L-1 for cell samples with good linearity behavior for all analytes in the concentration range of 0.04-200 µg L-1 in all the three matrices. The coefficient of determination for all the neurotransmitters was found in the range of (1) (R2) ≥ 0.996 to 0.999 for rat brain samples and (2) (R2) ≥ 0.991 to 0.999 for plasma and cell samples. The intra-day and inter-day variations were found less than (1) 1.78% and 8.94% for rat brain samples, (2) 1.83% and 8.37% for plasma samples and (3) 1.64% and 8.04% for cell samples respectively. The method has mean recoveries varied between (1) 81-128% for brain samples, (2) 88-107% for plasma samples and (3) 91-104% for cell samples at different spiking levels. The optimized and validated method was found free from matrix interferences and successfully applied for quantitative determination of 15 neurotransmitters in the rat brain, plasma and cell samples.

Comparison of two microextraction methods based on solidification of floating organic droplet for the determination of multiclass analytes in river water samples by liquid chromatography tandem mass spectrometry using Central Composite Design.

Two low density organic solvents based liquid-liquid microextraction methods, namely Vortex assisted liquid-liquid microextraction based on solidification of floating organic droplet (VALLME-SFO) and Dispersive liquid-liquid microextraction based on solidification of floating organic droplet(DLLME-SFO) have been compared for the determination of multiclass analytes (pesticides, plasticizers, pharmaceuticals and personal care products) in river water samples by using liquid chromatography tandem mass spectrometry (LC-MS/MS). The effect of various experimental parameters on the efficiency of the two methods and their optimum values were studied with the aid of Central Composite Design (CCD) and Response Surface Methodology(RSM). Under optimal conditions, VALLME-SFO was validated in terms of limit of detection, limit of quantification, dynamic linearity range, determination of coefficient, enrichment factor and extraction recovery for which the respective values were (0.011-0.219ngmL-1), (0.035-0.723ngmL-1), (0.050-0.500ngmL-1), (R2=0.992-0.999), (40-56), (80-106%). However, when the DLLME-SFO method was validated under optimal conditions, the range of values of limit of detection, limit of quantification, dynamic linearity range, determination of coefficient, enrichment factor and extraction recovery were (0.025-0.377ngmL-1), (0.083-1.256ngmL-1), (0.100-1.000ngmL-1), (R2=0.990-0.999), (35-49), (69-98%) respectively. Interday and intraday precisions were calculated as percent relative standard deviation (%RSD) and the values were ≤15% for VALLME-SFO and DLLME-SFO methods. Both methods were successfully applied for determining multiclass analytes in river water samples.

Ionic liquid based vortex assisted liquid-liquid microextraction combined with liquid chromatography mass spectrometry for the determination of bisphenols in thermal papers with the aid of response surface methodology.

A sensitive, rapid and efficient ionic liquid-based vortex assisted liquid-liquid microextraction (IL-VALLME) with Liquid Chromatography Mass spectrometry (LC-MS/MS) method is proposed for the determination of bisphenols in thermal paper. Extraction factors were systematically optimized by response surface methodology. Experimental factors showing significant effects on the analytical responses were evaluated using design of experiment. The limit of detection for Bisphenol-A (BPA) and Bisphenol-S (BPS) in thermal paper were 1.25 and 0.93µgkg-1 respectively. The dynamic linearity range for BPA was between 4 and 100µgkg-1 and the determination of coefficient (R2) was 0.996. The values of the same parameters were 3-100µgkg-1 and 0.998 for BPS. The extraction recoveries of BPA and BPS in thermal paper were 101% and 99%. Percent relative standard deviation (% RSD) for matrix effect and matrix match effects were not more than 10%, for both bisphenols. The proposed method uses a statistical approach for the analysis of bisphenols in environmental samples, and is easy, rapid, requires minimum organic solvents and efficient.