Authors:A. Rawat, P. Jojo, A. Kumar, and R. Prasad
The trace uranium concentrations have been determined in tobacco obtained from different brands of commercially available cigarette, beedi, chewing tobacco and also in pan masala, using fission track registration technique. Consumption of tobacco orally or by smoking may result in the intake of radioactive elements into the human body causing hazardous effects. External detector method was employed for the determination of uranium using Makrofol-KG as the fission track detector. The range of uranium was found to vary between 0.066–0.106 ppm, 0.042–0.079 ppm and 0.043–0.092 ppm, in tobacco from samples of cigarette, beedi and chewing tobacco, respectively, and between 0.073–0.203 ppm in pan masala samples.
Authors:P. Jojo, A. Rawat, Ashavani Kumar, and Rajendra Prasad
Water samples collected from various sources along the south-west coastal region of India have been analyzed for trace uranium concentration. Fission track registration technique with the Dry method has been used for the analysis. Uranium concentration was found to vary from 0.28±0.01 g/l to 2.71±0.41 g/l and was higher in sea water than in well, river and tap water, respectively.
Authors:Sayyada Khatoon, Manjoosha Srivastava, A. Rawat, and Shanta Mehrotra
The roots of
, known as ‘Bala’ in the Ayurvedic system of medicine, are used to treat a variety of ailments, including pulmonary tuberculosis, rheumatism, hematuria, urinary and heart diseases. The roots have recently been used to cure
disease and as a food supplement for fat loss. During a survey of Indian herbal drug markets it was observed that the roots and whole plants of other species of
S. acuta, S. cordata
, were being sold under the same vernacular name. In this context, HPTLC markers and a method for quantitative estimation of ephedrine, one of the therapeutically active constituents of this genus, have been developed. The study concluded that common and distinguishing bands were observed for all four
species in UV light at
= 366 nm. The roots of
had a similar HPTLC profile but the whole plant of
had characteristic blue bands at
0.60 and 0.81 and a red band at
0.87. Similarly, the whole plant of
can easily be differentiated on the basis of blue bands at
0.15 and 0.67; the roots can be differentiated by blue bands at
0.84 and 0.90. Although no characteristic bands were observed for
whole plant, the roots of this plant could also be identified by the presence of yellow and blue bands at
0.18 and 0.79, respectively. Amount of ephedrine varied in the four species studied. The maximum amount (0.112%) was found in
whole plant and the minimum amount (0.005%) in the roots of
Authors:G. Chourasiya, R. Duggal, C. Singh, A. Rawat, S. Aggarwal, and H. Jain
A direct evaporation method is described for the preparation of sources using stainless steel as the backing material and tetraethylene glycol (TEG) as a spreading agent in the presence of large amounts of uranium. It is shown that FWHM and tail contribution at the low energy peak due to energy degradation of the high energy peak can be optimized by heating the source under controlled conditions in a furnace at 500–600°C for about 15 min. An accuracy of 0.5–1% is demonstrated for the determination of238Pu/(239Pu+240Pu) alpha activity ratio in the U/Pu range of 10 to 1500 generally encountered in dissolver solution of irradiated fuel.
Authors:S. Aggarwal, G. Chourasiya, C. Singh, A. Rawat, S. Chitambar, and H. Jain
A method is described for the determination of plutonium concentration in the presence of a bulk of other impurities by isotope dilution mass spectrometry /IDMS/ using239Pu as a spike. The method involves the addition of239Pu spike / 90 atom%/ to samples with239Pu / 70 atom%/ and vice versa. After ensuring chemical exchange between the sample and the spike isotopes, plutonium is purified by conventional anion exchange procedure in 7M HNO3 medium.239Pu/240Pu atom ratio in the purified spiked sample is determined with high precision /better than 0.1%/ using a thermal ionization mass spectrometer. Concentration of plutonium in the sample is calculated from the changes in239Pu/240Pu atom ratio in the spiked mixture. Results obtained on different plutonium samples using239Pu as a spike are compared with those obtained by the use of242Pu spike. Precision and accuracy comparable to those achieved by using242Pu are demonstrated. The method provides an alternative in the event of non-availability of enriched242Pu or244Pu required in IDMS of plutonium and at the same time, offers certain advantages over the use of242Pu or244Pu spike.
Authors:S. Kumar, N. Rawat, A. Kanekar, B. Tomar, V. Manchanda, M. Sonavane, N. Sonar, and K. Raj
Diffusion of sodium in Mn and Ti bearing sodium borosilicate glass used for the immobilization of the high level waste at
the Waste Immobilization Plant, Tarapur has been studied by heterogeneous isotopic exchange using 24Na as the radiotracer for sodium. The temperature dependence of the self-diffusion coefficient of sodium in the glass was
found to follow Arrhenius equation below the glass transition temperature.
Authors:Ankita Misra, Amit Srivastava, Sharad Srivastava, and A.K.S. Rawat
Commelina benghalensis (Commelinaceae) is widely used as traditional and folklore medicine in India. In the present study, a reverse-phase high-performance liquid chromatography—photodiode array detection (RP-HPLC—PDA) method was developed for the separation, identification, and quantification of bioactive phenolics. Antioxidant potential was also accessed to validate the presence of identified markers. Method was developed on C18 column with 1% formic acid (in water) and acetonitrile as solvent system, and data acquisitions were achieved at wavelength of 285 nm. The developed method was also validated for accuracy, precision, robustness, limit of detection and quantification (LOD and LOQ), repeatability, and recovery according to International Conference on Harmonization (ICH) guidelines. In this method, five phenolics, viz., protocatechuic acid (0.033%), vanillic acid (0.262%), ferulic acid (0.365%), apigenin (0.126%), and kaempferol (0.544%), were quantified in linearity range of 0.2–1.0 μg with correlation coefficient of more than 0.9949. Relative standard deviation (RSD) (%), LOD, LOQ, and recovery (%) are within the acceptable limit. Besides that, methanolic extract shows the inhibition (%) range from 24.45 to 68.75% at 0.02–0.12 mg mL−1. IC50 of extract was observed at 46.75 μg mL−1, suggesting the promising activity in methanol extract. Hence, the proposed method for simultaneous quantification of five bioactive phenolics in the tuber of C. benghalensis using HPLC–PDA detection under the specified conditions is specific and accurate, and validation proves its selectivity and reproducibility.
Authors:S. Aggarwal, A. Almaula, P. Khodade, A. Parab, R. Duggal, C. Singh, A. Rawat, G. Chourasiya, S. Chitambar, and H. Jain
K-factors (= certified isotope ratio/observed isotope ratio) are determined for the isotope abundance measurements of uranium and plutonium by thermal ionisation mass spectrometry. An mdf of 0.07% and 0.18% per mass unit differing by a factor of about 3, is obtained for uranium and plutonium, respectively, employing double rhenium filament assembly in the ion source and Faraday cup as the detector using the presently available isotopic reference materials of uranium and plutonium.
Authors:A. Niranjan, J. Barthwal, A. Lehri, D. P. Singh, R. Govindrajan, A. K. S. Rawat, and D. V. Amla
Artemisia pallens L. (Compositae) is used in Indian traditional medicine to treat diabetes mellitus, jaundice, hysteria, body pain, and bacterial and fungal infections. A major cause of a variety of diseases is oxidative stress which is reduced by antioxidants such as polyphenols. These secondary metabolites are generally ubiquitous in plants and extensively used in the pharmaceutical, cosmetic, and food industries. In this study a simple and sensitive HPLC-UV-MS-MS-based method was developed for separation, identification, and quantification of polyphenols, for example gallic, protocatechuic, chlorogenic, caffeic, and ferulic acids, rutin, quercetin, and kaempferol. Amounts of polyphenols detected in 50% methanol-water extracts of the plant varied from 0.005% (kaempferol) to 0.24% (protocatechuic acid). Separation of the polyphenols was achieved on a reversed-phase C18 with a mobile phase prepared from 1% aqueous with acetic acid and acetonitrile at a flow rate of 0.6 mL min−1. The phenolic compounds were detected by UV absorption at 254 nm. The method was validated for linearity, accuracy, precision, LOD, LOQ, specificity, selectivity, and compound stability. Results from intra and inter-day validation (n = 6) showed the method was efficient and rapid. The optimized method was applied to extracts of A. pallens for identification and quantification of the polyphenols. The reference standards and their presence in A. pallens were confirmed by mass spectrometry.