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- Author or Editor: A. Garg x
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Abstract
A nondestructive NAA method based on the reaction 31P(n,γ)32P (T 1/2 = 14.23 d) has been developed where the product nucleus, a pure β-emitter with end point energy 1.71 MeV is measured by using an end window G.M. counter and an Al filter of 27 mg·cm−2. 32P was identified by measuring E β using Feather’s analysis and its half-life was found to be 15.3±0.2 days in standard reference materials (SRMs) and samples. For most reference materials (RMs) from NIST (USA) and IAEA (Vienna), our values agree within ±5% of the certified values. A variety of biological samples have also been analyzed and our values are in the range; medicinal herbs (n = 43), 0.29–5.23 mg/g; bhasmas (n = 19), 0.09–51.4 mg/g; vegetables (n = 8), 1.85–5.73 mg/g; lentils (n = 6), 2.1–5.5 mg/g; flours (n = 6), 1.3–3.3 mg/g; vegetarian diet (n = 5), 2.41–2.90 mg/g; fish (n = 43), 3.61–36.8 mg/g; human and animal milk (n = 6), 1.24–7.95 mg/g; commercial milk powders (n = 14), 2.76–11.9 mg/g; water from various sources (n = 14), 1–417 µg/l; human and animal blood (n = 9), 1.00–15.0 mg/g; cancerous and healthy breast tissue (n = 60), 1.00–8.63 mg/g; human hair (n = 43), 0.12–5.81 mg/g, where n is the number of samples analyzed. The method is simple, fast, and nondestructive and provides data within ±5% error limit with a detection limit of 0.1 mg/g.
Abstract
Traditional Indian medicinal herbs, used for strengthening the body immune system, are rich source of many essential nutrient elements in bioavailable form. Instrumental neutron activation analysis (INAA) employing short (5 minutes) and long (14 hours and 3 days) reactor irradiation followed by high resolution gamma-ray spectrometry has been used for the determination of Al, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cu, Eu, Fe, K, La, Mg, Mn, Na, P, Rb, Sb, Sc, Sm, Th, V and Zn in 15 medicinal herbs commonly used in Indian household for treatment of various ailments. viz. C. rhombifolia (Amaltas), W. somnifera (Ashwagandha), P. corylifolia (Bakuchi), T. cordifolia (Guduchi), M. fragrans (Jaiphal), N. jatamansi (Jatamansi), A. paniculata (Kalmegh), H. anticlysentrica (Kutaj), T. chebula (Laghu Haritaki), S. racemosa (Lodhra), A. indica (Neem), V. negundo (Nirgundi), H. indicus (Sariva), A. calamus (Vach) and E. ribes (Vidang). Several of herbs are enriched in Ca, Co, Cu, Mg, P, Fe, Mn and Zn, which play a vital role in biochemical and enzymatic processes. Jatamansi, often used as antibacterial, antipyretic and heart tonic is specially enriched in Co, Cr, Cu, Na, Mn, Fe, Rb and Zn. Also Guduchi and Laghu Haritaki are enriched in Ca and Mg, respectively. An attempt has been made to correlate elemental contents with the therapeutic importance of various herbs. Also our results for the participation in an Intercomparison Study of renewal of Pine Needles (SRM-1575a) from NIST, USA are presented.
Abstract
Brahmi (Bacopa monnieri) leaves, known as nervine tonic in Ayurveda, and its aqueous (BA), methanolic (BM) and aqueous–methanolic (BAM) extracts were analyzed for 7 minor (Al, Fe, Na, K, Ca, P, Cl) and 18 trace (As, Au, Ba, Br, Co, Cr, Cu, Hf, Hg, La, Mn, Rb, Se, Sm, Sr, Th, V, Zn) elements by INAA. BAM extract showed maximum contents of Na, K, Cl and significant amounts of Mn, Co, Zn. It was also found as effective scavenger of DPPH radicals with 33.5% total phenolic content, highest γ-ray radioprotective effect and higher anti lipid peroxidation activity.
Abstract
Trikatu, an Ayurvedic formulation of three dried powder spices, ginger, black pepper and pipali in equal proportion is widely used to promote digestion, assimilation and bioavailibility of food. It works synergistically, and hence, is more effective than an equal amount of any of its three ingredients taken separately. Five different brands and its three constituents were analyzed for 31 elements by instrumental neutron activation analysis (INAA) using 5-minute and 6-hour thermal neutron irradiation followed by high-resolution γ-ray spectrometry. Heavy toxic metals Cd, Ni and Pb determined by atomic absorption spectrometry (AAS) were found below permissible limits. Most elements in different brands vary in a narrow range. Ginger is particularly enriched in Ca, Fe, Mg and Mn whereas black pepper is enriched in Cr, Se, P and Zn. Cu/Zn shows linear relationship (r = 0.92) with Cu whereas Fe and Mn exhibit inverse correlation (r = −0.89) in different brands. Hydro distillation of pipali yielded an essential oil whereby 10 organic constituents were identified by GC-MS. Also barbituric and tannic acids were isolated from the aqueous methanolic extract of pipali.
Abstract
Radiochemical NAA methods have been developed for the simultaneous determination of Fe and Zn in biological samples. The method involves reactor irradiation, dissolution in 3M HCl and solvent extraction followed by counting on a scintillation gamma-ray spectrometer. Iron was separated with aqueous cupferron and extracted into chloroform while Zn was extracted with 2-thenoyl trifluoroacetone (TTA) into methyl isobutyl ketone (MIBK). Reaction conditions such as pH and the effect of solvents and various ions were studied using tracer activities. The methods have been employed for trace level determination of Fe and Zn in NBS, SRMs, Bowen's Kale, IAEA CRMs and other plant leaves.
Abstract
Phosphorus has been determined using the 
- emitter32P by instrumental neutron activation analysis (INAA) in several NBS and IAEA standards and samples of biological origin such as human and animal blood, cancerous tissue, edible plant leaves, diets, milk samples, etc. The method involves thermal neutron irradiation for 2–10 h in a reactor followed by
--counting on an end-window gas flow proportional counter using an aluminium filter. The results are within ±10% of the certified values in most cases.
Abstract
A radiochemical method for the determination of gold using198Au, has been developed. It is based on the synergistic extraction of Au(III) with thionalide (TA) in ethyl methyl ketone (EMK) or isobuthyl methyl ketone (IBMK) at pH 5.0.Effect of various parameters such as pH, nature of solvent and interferences due to other radionuclides have been studied. The method can be used up to 25 ng of Au.
Abstract
A radiochemical solvent extraction method has been developed for the determination of Mn(II) using54Mn tracer. Mn(II) is complexed with 2-thenoyltrifluoroacetone (TTA) at pH 8.5 and extracted in isobutyl methyl ketone (IBMK). Different parameters affecting the extraction, and interferences due to diverse ions have been studied. The method can be used for the determination of Mn in microgram amounts.
Abstract
Human, animal (cow, buffalo and goat) and commercial milk powders (for infants and adults) have been analyzed for 5 minor (Na, K, Mg, Cl and P) and 13 trace elements (Cr, Mn, Fe, Co, Cu, Zn, Cd, Hg, As, Se, Sb, Cs and Br) by instrumental and radiochemical neutron activation. Milk standards NIST SRM 1549 and IAEA A-11 along with diet standards RM 8431 a and IAEA H-9 were also analyzed for quality assurance. The method involves thermal neutron irradiation for 10 m, 1 h, 6 h and 1 week in a reactor followed by high resolution 
-spectrometry. Concentrations of Fe, Co, Zn, Sb, and Se were also determined by radiochemical solvent extraction. Mean concentrations of Na, K, Mg, P, Cl, Fe, Mn and Cu in human milk (colostrum) are comparable with that of a WHO/IAEA study. It has, however, lower contents of toxic trace elements (Cr, Cd, Hg, Br, Se, Sb and As) compared to breast tissue from the same area. Cow milk is richer in Na, K, Cl, Mn and Se but it has comparable amounts of Mg, Zn, Br, Fe and Sb with respect to breast milk. Significant differences have been observed for elemental concentrations of Na, K, P and Fe in commercial formula milk powders for infants and adults. Infant's milk powders contain all the nutrient elements in balanced amounts required for the higher growth rate of a child.
Abstract
In order to assess the source of pollutants and the atmosphere quality in and around a thermal power plant, fugitive dust particulates from seven different locations and ambient air dust from six locations have been analyzed for 32 elements (As, Au, Ba, Br, Ce, Cl, Co, Cr, Cs, Cu, Eu, Fe, Ga, Hg, Hf, K, La, Lu, Mg, Mn, Na, P, Rb, Sb, Sc, Se, Ta, Tb, Te, Th, W and Yb) by employing instrumental neutron activation analysis (INAA). The method involves the irradiation of samples and comparator standards in a thermal neutron flux range of 1012–1013
n·cm–2·s–1 in a nuclear reactor for 10 min and 1 day followed by high resolution 
-spectrometry. Wide differences have been observed in the mean elemental concentrations of Fe, Co, Br, Mn, As, P. Ba and Cu in fugitive and ambient dust particulates coliected from these different locations. Further, a comparison of the elemental contents of the dust particulates from the plant with environmental standards (Urban Particulate Matter, Coal Fly Ash, Vehicle Exhaust and Coal) show significantly lower or comparable amounts of toxic and pollutant elements in the environmental samples.
