Authors:R. Choudhury, R. Acharya, A. Nair, A. Reddy, and A. Garg
Four plant parts (leaves, roots, fruits and seeds) of twenty samples of sixteen antidiabetic herbs including three commercially
marketed capsules have been analyzed for 6 minor (Na, K, Ca, Cl, Mg, and P) and 21 trace (As, Ba, Br, Ce, Co, Cr, Cs, Cu,
Eu, Fe, Hg, La, Mn, Rb, Sb, Sc, Se, Sm, Th, V and Zn) elements by instrumental neutron activation analysis (INAA). Further,
Ni, Cd and Pb contents were determined by AAS. Elemental data were validated by simultaneously analyzing reference material
(RM), MPH-2 Mixed Polish Herbs. Several elements such as Cr and V (1–2 μg/g), Rb (10–40 μg/g), Cs (80–300 ng/g), Se (∼100
ng/g) and Zn (25–60 μg/g) play an important role in diabetes mellitus. Interelemental linear correlations have been observed
for Cu vs. Zn (r = 0.89) and Rb vs. Cs (r = 0.87). K/P ratio varies in a narrow range with a mean value of 6.2 ± 1.4. Toxic elements As and Hg were found in <1 μg/g
whereas Cd and Pb were in ∼5 μg/g and <10 μg/g, respectively.
Authors:Amol Shinde, R. Acharya, R. Verma, and A. Reddy
Nuclear and commercial grade graphite samples were analysed by instrumental neutron activation analysis (INAA) using high
flux reactor neutrons. Eleven elements (Na, K, As, Sc, Fe, Cr, Co, Zn, La, Ce, and Sm) were determined in eight samples of
graphite (two nuclear grade and six commercial grade) by irradiating at a neutron flux of 3 × 1013 cm−2 s−1 in CIRUS reactor and assaying the activity by high-resolution gamma ray spectrometry using 40% relative efficiency HPGe detector
coupled to an MCA. Concentrations of elements were determined by relative method of INAA. Results of both types of graphites
as well as detection limits achieved by INAA method are discussed in the paper.
Authors:A. Garg, R. Paul Choudhury, R. Acharya, and A. Reddy
Tobacco smoking/chewing has been a cause of concern because of it being related with oral cancer. It causes stimulation and
ill physiological effects. Ten different brands of spit tobacco, eight gutkaas and five paan masalas have been analyzed for
seven minor (Al, Na, K, Ca, Cl, Mg, and P) and 17 trace (As, Ba, Br, Co, Cr, Cs, Cu, Eu, Fe, Hg, La, Mn, Rb, Sb, Sc, Th, and
Zn) elements by instrumental neutron activation analysis. Also Ni and Pb were determined by atomic absorption spectrophotometry.
Concentration of Cd was below detection limit (<10 mg kg−1) in the tobacco samples. Mg, generally added as MgCO3 to prevent caking, is present as minor constituent in spit tobacco and gutkaas but is below detection limit (<1 g kg−1) in paan masalas. Most elemental concentrations vary in a wide range depending on the nature of chewing tobacco. Spit tobacco
has been found to be more enriched in essential elements (Ca, K, Na, P, Mn, and Rb), whereas gutkaas contain higher concentrations
of Fe, Cr, Cu, and Zn. Paan masalas contain lower contents of other elements but higher content of Hg. Gutkaas also contain
higher amounts of As and Pb. Further glutamic acid has been separated from tobacco leaves and characterized as it might bind
with some elements.
Authors:K. Swain, Nicy Ajith, R. Acharya, R. Verma, and A. Reddy
Large sample neutron activation analysis of dross from India Government Mint, Mumbai was carried out for quantification of
gold (Au) and silver (Ag) using graphite reflector position of Advanced Heavy Water Reactor critical facility at Bhabha Atomic
Research Centre, Mumbai. The k0-based internal monostandard NAA was used to calculate concentration ratios of Au and Ag with respect to sodium (Na), which
was used as an internal monostandard. The concentration ratio values of Au to Na of varying mass of dross showed that mass
≥2 g was the representative sample size for analysis. Concentrations of gold and silver were found to be in the range of 200–400
and 1200–1700 mg kg−1, respectively in three different samples.
Authors:R. Acharya, P. Burte, A. Nair, A. Reddy, and S. Manohar
Multielement analysis was carried out in two samples of natural rubies obtained from Kenya and Tanzania and a synthetic ruby obtained locally. The trace element profile was used to characterise the ruby samples. Instrumental Neutron Activation Analysis (INAA) by the single comparator (K0 method) was used to determine the concentrations of 22 elements with gold as the comparator. High resolution -ray spectrometry was employed for radiometric assay of the activation products. The accuracy and precision were evaluated by analysing standard reference materials such as USGS-W-1 and AGV-1 and were found to be satisfactory.
Authors:Rupali Lagad, D. Alamelu, R. Acharya, and Suresh Aggarwal
Instrumental neutron activation analysis (INAA) was employed to determine concentrations of 19 elements (As, Ba, Br, Ce, Co,
Cr, Cs, Fe, K, La, Mn, Na, Nd, Rb, Sc, Sm, Th, Yb and Zn) in a large number (55) of tea samples (from market as well as virgin
tea leaves) from different locations in India (Assam, Darjeeling, Munnar and Kangra). The results obtained in the present
work are compared with those reported in literature. The concentration levels, their variations with collection locations
and the correlations among different elements in these samples are discussed.
Authors:R. Acharya, A. Nair, K. Sudarshan, A. Goswami, and A. Reddy
A summary of k0-based R&D work on neutron activation analysis (NAA), internal mono standard NAA (IM-NAA) and prompt gamma-ray NAA (PGNAA)
is presented. The k0-based NAA was standardized by characterizing irradiation sites of research reactors, validated using reference materials
and applied to samples of different origin. Recently IM-NAA method was developed, validated for small and large size samples
and applied for the analysis of large size as well as non-standard geometry samples. Studies on PGNAA included characterization
of neutron beam, determinations of detection efficiency and prompt k0-factors, and analytical applications.
Authors:A. Nair, A. Reddy, R. Acharya, P. Burte, and S. Manohar
A chemical neutron activation analysis method to determine trace amounts of palladium present in the uranium ores has been
developed. Palladium was concentrated on an anionic exchanger to purify from large amounts of uranium, iron and copper that
were present in the ore. The resin in which Pd was adsorbed was neutron irradiated and the activation product109Pd was assayed through its daughter109mAg by low energy photon spectrometry to estimate palladium. Both the 88 keV gamma-line and the 22 keV X-ray line (arising
out of the internal transition of109mAg) were used to arrive at the concentration values by a standard comparison technique. A thin window Si(Li) detector and
an HPGe detector were used for the radioactive assay. Detection limits and the advantage of using the X-ray line of Ag over
that of the gamma-line were discussed. An absolute detection limit of 0.12·10−9 g could be arrived at by the use of the 22.10 keV X-ray line in an interference-free condition.
Authors:S. Kulkarni, R. Acharya, N. Rajurkar, and A. Reddy
Studies on bioaccessibility of elements were carried out by in-vitro gastrointestinal digestion simulation method combined
with neutron activation analysis (NAA) using NH4HCO3 as an alternate base to commonly used base of NaHCO3. The effect of two bases namely NaHCO3 and NH4HCO3 on the bioaccessibility of the elements namely Br, Fe, K, La, Na, Rb, Sm and Zn from wheat seeds, fresh wheatgrass and commercial
wheatgrass tablet was investigated. The bioaccessible concentrations of the elements were determined by neutron activation
analysis (NAA). The bioaccessible concentrations of samples digested using NH4HCO3 were found to be higher by 10–15% for most of the elements than that observed using NaHCO3. In the case of fresh wheatgrass, the differences were as high as 50%. The present study indicated that NH4HCO3 can be used as a base instead of NaHCO3 in in-vitro gastrointestinal digestion simulation method.