Moina Akhtar Mughal

On-line preconcentration and determination of ultra trace amounts of mercury using surfactant coated alumina modified by dithizone with cold vapor atomic absorption spectrometry

The potential of an inexpensive dithizone immobilized on ammonium lauryl sulfate alumina adsorbent to separate and preconcentrate traces of mercury from vegetables and ground water has been evaluated. A cartridge filled with 100 mg of adsorbent was incorporated to an on-line vapor generation accessory system. Traces of mercury in sample solutions were pumped through the cartridges for 2 min (flow rate of 5 mL min−1) and then eluted from the cartridges with 1 M hydrochloric acid for 1 min at a flow rate of 1 mL min−1. At the same time that mercury is eluted from the cartridges, the eluate is mixed with a 0.02% (m/v) sodium borohydride solution and the mercury cold vapor is swept through the atomization cell with a nitrogen flow of 50 mL min−1. The overall procedure (mercury separation–preconcentration and mercury cold vapor generation–atomization) is completed in around 3 min. The developed method achieves an enrichment factor of 125 with a limit of detection of 0.12 ng mL−1. The repeatability and the accuracy of the overall procedure were successfully assessed.

Evaluation of lead levels in biological samples of mentally retarded children in different stages using advanced extraction method.

In present study the lead (Pb) levels has been assessed by analyzing the scalp hair and blood samples of mentally retarded/intellectual disabled (MR/ID) children of both genders, age ranged 3-8 years. For comparative purpose, healthy age matched children were also selected. The cloud point extraction of Pb from digested biological samples was carried out by complexed with ammonium pyrrolidinedithiocarbamate. The complexed analyte was subsequently isolated from the aqueous matrix in the micelles of a non-ionic surfactant (Triton X-114). Dilution of the surfactant-rich phase with acidified ethanol was performed after phase separation, and the Pb content was measured by flame atomic absorption spectrometer. Factors affecting the cloud point extraction were evaluated and optimized. The proposed procedure allowed the determination of lead in certified standard and real samples with detection limits of 0.834μgL(-) and enhancement factor 55. The results were compared with those of healthy children have same age, socioeconomic status and residential areas.

Synthesis, Characterization and Antibacterial and Antifungal Studies of Schiff base Polymers derived from Methylene bis Cinnamaldehyde

The present study explores the synthesis and characterization of all the compounds via Carbon-Hydrogen-Nitrogen (C.H.N.) analysis with infrared, ultraviolet spectroscopy. Antibacterial and Antifungal studies of these compounds against different antibacterial and antifungal microorganisms gave important findings. Six new Schiff base polymers Poly 4,4-methylene bis(cinnamaldehyde) 1,2-diiminopropane (PMbCPn), Poly 4,4-methylene bis(cinnamaldehyde) 1,3-diiminopropane (PMbCPR), Poly 4,4-methylene bis(cinnamaldehyde) ethylenediimine (PMbCen), Poly 4,4-methylene bis(cinnamaldehyde) 1,2-phenylenediimine (PMbPCPh), Poly 4,4-methylene bis(cinnamaldehyde) Urea (PMbCU), Poly 4,4-methylene bis(cinnamaldehyde) Semicarbazide (PMbCSc), and Poly 4,4-methylene bis(cinnamaldehyde) Thiosemicarbazide (PMbCTSc), were prepared by polycondensing these polymers with methylene bis cinnamaldehyde by a general method. The monomer and Schiff base polymers presented considerable antimicrobial results.

Chemical composition of the essential oils from Tamarix dioica and determination of its antibacterial activity

ABSTRACT In this study, investigations of hydro-distilled essential oils of Tamarix dioica flowers and leaves performed by gas chromatography-mass spectrometry (GC-MS) revealed 31 volatile constituents. Nearly 24 (comprising 77.15% of the total volatiles) and 14 compounds (encompassing 63.15% of the total volatiles) were identified in flowers and leaves, respectively. Major constituents in flower were 1-hexadecene (6.93%), hexahydrofarnesyl acetone (5.64%), octadecane (5.60%), dodecanoic acid (5.22%), E-15-heptadecenal (4.98%), docosane (4.76%), 2-methoxy-4-vinylphenol (4.44%), 1-tetradecene (4.29%), tetracosane (4.00%), 1-docosene (3.89%), hexadecane (3.76%), nonanal (3.69%), nonanoic acid (1.33%), dihydroactindiolide (3.33%), and cyclotetracosane (3.04%), whereas the major constituents in leaves were 2-methoxy-4-vinylphenol (17.70%), dihydroactindiolide (10.27%), megastigmatrienone (5.53%), 1-hexadecene (5.10%), β-lonone (4.28%), safranal (3.35%), vitispirane (3.35%), trans-geranylacetone (2.72%), and hexahydrofarnesyl acetone (2.03%). These essential oils were screened in vitro against gram negative (G−ve) bacteria Escherichia coli (E. coli) and gram positive (G+ve) bacteria Staphylococcus aureus (S. aureus) by using disc diffusion method to determine minimum inhibitory concentration (MIC). However, it is noteworthy that essential oils from Tamarix dioica flower and leaves showed a higher activity against E. coli (MIC at 10 μg/mL) compared to S. aureus (MIC at 100 μg/mL).

Preparation, Characterization, Viscosity and Thermal Analysis of a Schiff-Based Resin derived from 2-Methoxy-1-Napthaldehyde

A New Schiff based resin Poly-methylene bis (2-methyoxy-1-napthaldehyde) 1, 2-propylenediimine (PMBMNPn) was synthesized by reacting with Formaldehyde (HCHO). The synthesized resin was categorized through elemental micro-analysis and Fourier transformation. The infrared, ultraviolet and visible spectroscopic analysis TGA/DTA and Viscometric studies were also carried out. The results of Carbon-Hydrogen-Nitrogen (CHN) Analysis were in good agreement with the considered values and reinforced the formation of the prepared resin. The resin indicated more strong absorption around 16 to 35 cm -1 of stretching vibration than the Schiff base, confirming the structure of synthesized resin. A shift of absorption maxima towards longer wavelength within 10 to 34nm perceived in the initial 3 bands of compound PMBMNPn in comparison with BMNPn. A significant elevation in  for resin was seen as compared to Schiff base.

Essential long chain polyunsaturated fatty acids in muscle tissue of freshwater fish Labeo calbasu under different cooking processes

The effect of different cooking methods (Raw, steaming, microwave cooking, baking, grilling, pan frying and deep frying) on proximate composition and fatty acid profile of Labeo calbasu fish species from Pakistan were analyzed to determine the nutritional qualities in terms of the long chain n-3 PUFA particularly EPA and DHA. In all cooking methods moisture content decrease and protein content increased as compare to raw sample. The moisture content of fish sample seemed to be inversely related to the total extractable lipid content. In steamed, microwave, baked, grilled and pan fried methods MUFA were the abundant fatty acids followed by SFA and PUFA. Deep fried fish sample had the opposite trend having highest PUFA as contrast to MUFA and SFA. Long chain n-3 PUFA were found higher in contrast to n-6 PUFA in all other cooking methods excluding deep frying. The results indicates that steamed and grilled cooking are the best cooking method for healthy eating as they contain more n-3 PUFA (EPA and DHA). Losses of n-3 content in pan fried and deep fried fish were higher than those of fish cooked by other methods.