Khurshid Ali

Study of thallium (III) adsorption onto multiwall carbon nanotubes

Multiwall carbon nanotubes (MWCNTs) oxidized by H2SO4, KMnO4, and HNO3 were used as sorbents and their sorption abilities for Tl(III) were compared with raw MWCNTs. The Langmuir model was used for the calculation of the amount of Tl(III) sorbed on the surface of MWCNTs. The acidic oxidation treatment of MWCNTs yielded a large number of functional groups, leading to a sharp increase in Tl(III) adsorption. Maximum adsorption of Tl(III) was recorded at a pH value of 7. The maximum amounts of Tl(III) sorbed on raw MWCNTs, H2SO4-oxidized, KMnO4-oxidized and HNO3-oxidized MWCNTs calculated by the Langmuir model were 3.0, 11.7, 21.6 and 31.5 mg/g, respectively. The MWCNTs oxidized by HNO3 showed the best sorption performance for Tl (III) ions.

LIPID PROFILE AND GLYCOSYLATED HEMOGLOBIN STATUS OF GESTATIONAL DIABETIC PATIENTS AND HEALTHY PREGNANT WOMEN

AIM Lipid profile and glycosylated hemoglobin level changes in gestational diabetes. The extent to which this alteration takes place is still not clearly documented. MATERIALS AND METHODS To add a clear answer to this question, lipid profile parameters, and glycosylated hemoglobin status were determined in patients with gestational diabetes mellitus and compared to healthy pregnant women (controls). RESULTS Fasting plasma glucose levels, plasma glucose levels 1 hour, and plasma glucose levels 2 hours after 75 gm oral glucose administration (oral glucose tolerance test) were significantly higher in patients with gestational diabetes as compared to controls. Glycosylated hemoglobin was significantly higher in gestational diabetes than in controls. It was observed that there was a significant increase in serum cholesterol and serum triglyceride level in cases with gestational diabetes when compared to healthy pregnant women. CONCLUSION The results of our study suggest that abnormal glucose levels, glycosylated hemoglobin, serum cholesterol, and serum triglycerides play an important role in pathophysiology of gestational diabetes, and therefore, extensive studies are required. Early diagnosis of gestational diabetes will decrease adverse neonatal and maternal outcomes.

Thio-pyridinium capped silver nanoparticle based supramolecular recognition of Cu(I) in real samples and T-lymphocytes

The newly synthesized cationic heterocyclic ligand 2 was characterized by NMR and mass spectrometric techniques. It showed great tendency to stabilize readily reducible silver salts and form silver nanoparticles (ThPy-AgNPs). The photophysical properties of these nanoconjugates (ThPy-AgNPs) were studied by AFM, UV-vis absorption and FT-IR spectroscopy. Moreover, the silver nanoparticles (ThPy-AgNPs) decorated with 2 recognizes Cu(I) in the presence of other competing metal ions making it a highly selective and sensitive nanosensor for the recognition of Cu(I) with a limit of detection of 2 μM which is much lower than its threshold level (∼20 μM) in drinking water permitted by the U.S. Environmental Protection Agency (EPA). The nanosensor (ThPy-AgNPs) was screened in pH range of 1–12 and the accuracy was determined by recovery studies. Finally, atomic force microscopy was used to study the interaction of ThPy-AgNPs with Cu(I) in T lymphocytes. The ThPy-AgNPs also selectively recognized Cu(I) in human blood plasma. The utility of this system was also evaluated in real water samples.

Preparation and characterization of a green nano-support for the covalent immobilization of glucoamylase from Neurospora sitophila

The preparation of green nano supports for the covalent immobilization of enzymes is of special interest both from the economic and environmental point of view. In this contribution, we report on the synthesis of phytochemicals coated silver nanoparticles, which were used as a novel green support for the covalent immobilization of glucoamylase isolated from Neurospora sitophila. The aqueous extract of Fagonia indica was used as a source of reducing and capping agents for the reduction of silver ions into silver nanoparticles. The prepared nanoparticles were characterized by various analytical techniques. UV-visible spectroscopy was used to detect the characteristic surface plasmon resonance bands (426, 438nm) of the silver nanoparticles. The biosynthesized silver nanoparticles were mostly spherical in shapes with an average particle size of 30-40nm (TEM and DLS measurements). X-ray diffraction and energy dispersive X-ray studies confirmed the face centered cubic crystalline form and elemental composition of the biogenic silver nanoparticles respectively. FTIR study revealed that plant polyphenolics and protein were mainly involved in the reduction and capping of silver ions. Glucoamylase from Neurospora sitophila was covalently immobilized to these nanoparticles via EDC (1-(3-(dimethylamino) propyl) 3-ethylcarbodiimidehydrochloride) coupling reaction. The immobilized enzyme exhibited higher pH and thermal stabilities as compared to the free enzyme. The kinetic constant (KM) value for the immobilized glucoamylase was higher (0.73mg/mL) than its free counterpart (0.44mg/mL), whereas the Vmax value was slightly higher for the immobilized glucoamylase. The findings of this study conclude that the newly developed green method for the synthesis of green nano-support is simple, cost effective and could be successfully used for the immobilization of various enzymes and other macromolecules.

Removal of Chromium(VI) from Industrial Effluents Through Supported Liquid Membrane Using Trioctylphosphine Oxide as a Carrier

The present study describes extraction of chromium(VI) through supported liquid membrane (SLM), Celgard 2400, which was impregnated with trioctylphosphine oxide (TOPO) dissolved in toluene. The stripping phase was comprised of diphenylcarbazide (DPC) in sulfuric acid (H2SO4) whereas the feed phase consists of potassium dichromate (K2Cr2O7) and hydrogen peroxide (H2O2). The effects of concentrations of chromium, TOPO, DPC, and H2SO4 have been studied in order to evaluate the transport efficiency of chromium(VI) ion. The optimum experimental conditions for the chromium(VI) extraction were established as follows: 19.2 × 10−4 mol L-1 chromium ion, 1.5 mol L-1 H2O2 concentration in the feed phase, 0.1 mol L-1 TOPO concentration in the membrane phase and 0.001 mol L-1 DPC and 1.5 mol L-1 H2SO4 as stripping phase. The measurements of percent recovery, distribution coefficient, flux and permeability were made at the given optimized conditions. The extraction time and membrane stability were also investigated. Extraction efficiency of 80% was recorded in 180 min and the SLM system was found stable up to 10 days. The optimized SLM system was then applied on the paint industry wastewater; about 80% of chromium(VI) was successfully removed from the wastewater.

Physico-chemical Study of Bagasse and Bagasse Ash from the Sugar Industries of NWFP Pakistan and Remediation of Environmental Problems Caused by Refused Bagasse Ash

Bagasse ash from the local sugar mills of NWFP (Pakistan) has been analyzed both physically and chemically. The moisture, ash contents, loss on ignition (LOI), volatile matter and calorific value have been determined. The qualitative and quantitative analysis was carried out by x-ray flourimeter (XRF) and carbon sulfur detector. The physical parameters were determined by thermogravemetric analyzer (TGA) and bomb calorimeter. The bagasse was also analyzed for ash and moisture contents which were found to be 3.66 and 9.47% respectively. The bagasse ash was found to consist of 86.69% ash, 13.45% loss on ignition (LOI) and 50 kcal/kg calorific value. The chemical constituents of bagasse ash were found to comprise of SiO2, Al2O3, Fe2O3, CaO, MgO, Na2O, K2O, carbon and sulfur.