Sanjukta A. A kumar | Homi Bhabha National Institute (HBNI, BARC, MUMBAI) (original) (raw)

Papers by Sanjukta A. A kumar

Research paper thumbnail of A fluoride ion selective Zr(iv)-poly(acrylamide) magnetic composite

RSC Advances, 2014

ABSTRACT A fluoride ion selective magnetic sorbent has been synthesized by the encapsulation of F... more ABSTRACT A fluoride ion selective magnetic sorbent has been synthesized by the encapsulation of Fe3O4 nanoparticles in a network of Zr(IV) complexed poly(acrylamide) (Zr–PAM). This magnetic sorbent has been found to be efficient for the selective preconcentration of fluoride ions from natural waters. The Zr–PAM/Fe3O4 composite has been characterized using various physico-chemical techniques i.e. energy dispersive X-ray fluorescence (EDXRF), scanning electron microscopy (SEM), Fourier transform infra-red spectroscopy (FTIR) and a vibrating sample magnetometer (VSM). The Zr–PAM/Fe3O4 composite developed in the present work retains the super paramagnetic properties of Fe3O4 nanoparticles, and the results reveal that the sorption is rapid. The composite has a considerably higher fluoride sorption capacity (124.5 mg g-1) compared to other super-paramagnetic fluoride sorbents reported in the literature. Repeated sorption–regeneration cycles seem to suggest reusability of the sorbent for fluoride removal from natural waters, as well as other aqueous solutions having pH in the range 1–9.

Research paper thumbnail of Fusion method for sample preparation for isotopic composition determination of boron in refractory materials by thermal ionization mass spectrometry with validation using dissolved and purified samples

International Journal of Mass Spectrometry

Abstract Various refractory samples of boron such as titanium borides, rare earth borides, boron ... more Abstract Various refractory samples of boron such as titanium borides, rare earth borides, boron carbides having natural and non-natural isotopic composition were analysed by thermal ionization mass spectrometry as Na2BO2+ ions. Samples were fused with Na2CO3 directly on the filament after adjusting the B/Na mole ratio to 2 and in certain cases modifications in the loading technique were required to obtain precise 10B/11B isotopic ratio. A few of the samples expected to have natural 10B/11B ratio were observed to be slightly enriched in 10B. Dissolved samples as well as boron purified by extraction with 5% 2-Ethyl Hexane Diol(EHD) were analysed for 10B/11B ratio to ascertain the accuracy of the results obtained by the direct fusion method. Precision of about 0.02% (1RSD) was obtained for 10B/11B isotopic ratio measured in all the three types of samples. A good agreement of the dissolved sample and purified boron fraction with the directly fused sample validated the direct fusion method as a fast and reliable technique for isotopic analysis of boron in refractory samples.

Research paper thumbnail of Understanding the As(III) oxidative performance of MnO2 polymorphs (α, β, and γ) and synthesis of an efficient nanocomposite of iron ore slime derived 2-line ferrihydrite and γ-MnO2 for sequestration of total arsenic from aqueous solution

Chemical Engineering Journal, 2022

Research paper thumbnail of A Facile Strategy for Preparation of Yttrium-90 Therapeutic Sources for Radionuclide Therapy

Cancer Biotherapy and Radiopharmaceuticals, 2022

Background: Mold brachytherapy using high-energy b-emitting radioisotopes is a promising treatmen... more Background: Mold brachytherapy using high-energy b-emitting radioisotopes is a promising treatment modality for skin cancers and keloids. Simple methodologies for consistent and stable incorporation of radionuclides into the matrix are desired for preparation of therapeutic sources. Methods: The authors report a facile strategy for the stable incorporation of Yttrium-90 (90 Y) into amidoximefunctionalized polyacrylonitrile-polyvinylidene fluoride (PAN-PVDF) membranes. The strategy consisted of surface modification of PAN-PVDF membranes by reaction with hydroxylamine, characterization of the functionalized membranes, and optimization of experimental variables for maximum loading of 90 Y onto the membranes. Quality control tests essential for confirming the suitability of the 90 Y therapeutic sources for human application, such as uniformity of activity distribution, absence of leaching of activity, and estimation of surface contamination, were performed. Theoretical calculations to estimate the dose imparted by the 90 Y therapeutic sources at varying depths of tissue were also carried out to predict the possible therapeutic outcome of treatment. Results: A facile method for large-scale preparation of 90 Y-based mold brachytherapy sources could be established. Conclusions: The source fabrication methodology standardized in this work could be tailored for fabrication of custom-made 90 Y sources for individualized treatment of superficial tumors, Bowen's disease, and keloids.

Research paper thumbnail of Titanium dioxide, layered hydrazinium titanate and eggshell as potential sorbents for remediation of chromium from aqueous stream

Separation Science and Technology, 2020

Titanium dioxide (TiO 2), layered hydrazinium titanate (LHT) and eggshell were studied for sorpti... more Titanium dioxide (TiO 2), layered hydrazinium titanate (LHT) and eggshell were studied for sorption of chromium from aqueous streams. Among the three sorbents, the eggshell, a bio-waste is found to have maximum sorption capacity of 315 mg g −1. Sorption of Cr(III) as well as Cr(VI) was found to be spontaneous on LHT while TiO 2 and eggshell can accumulate only Cr(III). However, sorption of Cr(VI) on these was ensued after in situ reduction of Cr(VI) to Cr(III). Experimental result indicates absence of any interference from ions commonly present in ground water.

Research paper thumbnail of Quantitative Evaluation of 28 Mineral Elements by Inductively Coupled Plasma/Mass Spectrometry and Its Application in Source Identification of Indian Opium

Journal of AOAC INTERNATIONAL, 2005

An analytical method based on inductively coupled plasma/mass spectrometry (ICP/MS) was developed... more An analytical method based on inductively coupled plasma/mass spectrometry (ICP/MS) was developed for the determination of 28 mineral elements (Cr, Mn, Co, Ni, Cu, Zn, Ga, Sr, Cd, Ag, Ba, Pb, Bi Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) in Indian opium samples. The detection limits were found to be in the range of 0.0008–0.45 ng/mL. The recoveries of spiked samples for each element were found to be in the range of 83–106%, with a precision of less than 9%. A total of 124 opium samples from India were analyzed for the distribution pattern of the 28 mineral elements. Quantitative elemental data were subjected to chemometric analysis in order to determine an optimal classifier to evaluate the source of Indian opium. The study indicated that mineral elements might not be the suitable discriminators for the discrimination of licit opium-growing divisions of India. However, the methodology developed and the analytical data on elemental profile may find important foren...

Research paper thumbnail of Remediation of chromium(VI) ions as chromium oxide xerogel via gamma-radiolysis of aqueous waste discharge

Separation and Purification Technology, 2019

Remediation of chromium(VI) ions as chromium oxide xerogel via gamma-radiolysis of aqueous waste ... more Remediation of chromium(VI) ions as chromium oxide xerogel via gamma-radiolysis of aqueous waste discharge, Separation and Purification Technology (2019), doi:

Research paper thumbnail of Exploring Nanostructured Zr/Cu Composite Oxide (NZCO) as an Efficient Adsorbent for Removal of As(III) and As(V) from Aqueous Solution

ChemistrySelect, 2019

Consumption of arsenic contaminated water induces and aggravates major health problems in humans.... more Consumption of arsenic contaminated water induces and aggravates major health problems in humans. In this report, we have successfully synthesized nanostructured Zr/Cu composite oxide (NZCO) by ultrasonically assisted hydrothermal process for total arsenic sequestration. Various batch experiments were performed with NZCO to determine its adsorption efficacy for As(III) and As(V) species. NZCO demonstrated outstanding performance in removing arsenic species from water with maximum adsorption capacities of 72.25 mg g−1 and 107.5 mg g−1 for As (III) and As (V) respectively under optimized conditions. The adsorption kinetics was closely fitted to pseudo‐second order model and adsorption isotherms were well described by D−R isotherms model. Meanwhile, the adsorption tests performed on naturally occurring ground water samples confirmed the effectiveness of NZCO in remediating total arsenic level below the prescribed limit of WHO‐MCL (0.01 mg L−1). The adsorption mechanisms study exhibits ...

Research paper thumbnail of Corrosion behavior analyses of metallic membranes in hydrogen iodide environment for iodine-sulfur thermochemical cycle of hydrogen production

International Journal of Hydrogen Energy, 2018

Research paper thumbnail of Preparation of Radioactive Skin Patches Using Polyhydroxamic Acid-Grafted Cellulose Films Toward Applications in Treatment of Superficial Tumors

Cancer biotherapy & radiopharmaceuticals, 2017

The primary objective of this investigation is the development of a strategy for the synthesis of... more The primary objective of this investigation is the development of a strategy for the synthesis of polyhydroxamic acid (PHA)-grafted cellulose film, its characterization, and evaluation of its usefulness for the preparation of 177Lu skin patches for superficial brachytherapy applications. PHA-grafted cellulose films were synthesized and characterized by Fourier transformed infrared spectrometer analysis and visual color test with Fe(III) solution. Uptake of 177Lu on the PHA-grafted cellulose was investigated by varying the experimental conditions such as the pH of feed solution, amount of nonradioactive Lu carrier, time, and temperature of the reaction. Under the optimized conditions, >95% loading of 177Lu on the PHA-cellulose film could be achieved. Autoradiography studies of 177Lu-PHA-cellulose film confirmed the uniform distribution of 177Lu on the surface. Energy dispersive X-ray analysis of nonradioactive Lu-PHA-cellulose film confirmed the loading of Lu on PHA-cellulose film...

Research paper thumbnail of Optode sensor for on-site detection and quantification of hydroxide ions in highly concentrated alkali solutions

RSC Advances, 2015

Development of a colorimetric strip sensor for visual detection and quantification of hydroxide i... more Development of a colorimetric strip sensor for visual detection and quantification of hydroxide ions in highly concentrated alkali solutions.

Research paper thumbnail of Direct determination of uranium in seawater by laser fluorimetry

Talanta, 2008

A method for estimation of uranium in seawater by using steady state laser flourimetry is describ... more A method for estimation of uranium in seawater by using steady state laser flourimetry is described. Uranium present in seawater, in concentration of approximately 3 ng ml −1 was estimated without prior separation of matrix. Quenching effect of major ions (

Research paper thumbnail of Recovery and pre-concentration of uranium from secondary effluent using novel resin

International Journal of Nuclear Desalination, 2010

... 1, pp.28–36. Biographical notes: Sangita Pal joined BARC as Scientific Officer in 2006, after... more ... 1, pp.28–36. Biographical notes: Sangita Pal joined BARC as Scientific Officer in 2006, after completing PDF from HLRC. ... He was Chairman of International Nuclear Desalination Advisory Group (INDAG) of International Atomic Energy Agency (IAEA) for the term 2005–2008. ...

Research paper thumbnail of Development of a visual optode sensor for onsite determination of Hg(II)

Sensors and Actuators B: Chemical, 2015

A color changeable cellulose triacetate (CTA) membrane based optode has been developed for the hi... more A color changeable cellulose triacetate (CTA) membrane based optode has been developed for the highly selective and sensitive determination of Hg(II) ions in aqueous solutions. The sensing layer of the optode consists of phenylthiosemicarbazide derivative of rhodamine 6G immobilized in a plasticized cellulose triacetate membrane. The colorless optode film on reaction with Hg(II) turned pink in color and the intensity of the color was found to be directly proportional to the amount of Hg(II). The sensing mechanism is based on the mercury induced spirolactum ring opening followed by its cyclization to form highly conjugated system which leads to the development of pink color. Various experimental parameters such as pH, optode composition and response time have been optimized. Under these conditions the sensor showed a wide linear dynamic range of 10 to 5000 ng mL-1 Hg(II) with a detection limit of 1.3 ng mL-1. In addition to its stability and reproducibility, optode showed a high selectivity towards Hg(II) ions as compared to other co-existing ions in real water samples. The developed optode is suitable for rapid and on-site detection of Hg(II) ions in a variety of aqueous samples. The sensor was successfully applied for the determination of Hg(II) ions in ground water samples.

Research paper thumbnail of Functionalized polymer sheet sorbent for selective preconcentration and determination of mercury in natural waters

Anal. Methods, 2014

Mercury is considered as a highly toxic and widespread heavy-metal pollutant. In the present work... more Mercury is considered as a highly toxic and widespread heavy-metal pollutant. In the present work, two flat-sheet polymer sorbents have been synthesized for the selective preconcentration of mercury from natural waters. These are a silver nanoparticle (AgNP)-embedded poly(acrylamide)-grafted poly(propylene) sheet (Ag-PAM-PP) and a 1,8-octanedithiol-functionalized gold-coated poly(propylene) sheet (HS-octyl-S-Au-PP). The functional groups acrylamide and thiol provide the binding sites for Hg2+ ions; whereas silver nanoparticles reduce Hg2+ to Hg0 and it is held on the sheet by amalgam formation. Various factors that influence the preconcentration of Hg2+ from aqueous solution were investigated. Based on the comparison of the experimental results, it was observed that Ag-PAM-PP had superior performance for uptake of Hg2+ from natural water samples in terms of sorption capacity, sorption kinetics and working pH range. The uptake of Hg2+was found to be pH dependent with a maximum of 95% at pH 7.5. The preconcentration of Hg2+ from a large volume of aqueous solution was used to extend the lower limit of the concentration range that can be quantified by EDXRF and CV-AAS. The sorbed Hg(II) from aqueous samples was quantitatively detected within 1 min using EDXRF. The LOD (3σ) for CV-AAS (RSD = 2%) and EDXRF (RSD = 5%) were 6 and 30 μg L−1, respectively. The method was applied for the determination of Hg2+ in groundwater and seawater samples in the presence of a high concentration of interfering ions.

Research paper thumbnail of A visual strip sensor for determination of iron

Analytica Chimica Acta, 2014

A visual strip sensor for on-site detection of iron has been developed and made. The sensor is ea... more A visual strip sensor for on-site detection of iron has been developed and made. The sensor is easy to synthesize, portable and recyclable with shelf life >1 year. Visual detection limit for iron using the present sensor is 50 ng mL À1. Visual strip sensor was applied to ground water and fruit juices.

Research paper thumbnail of Determination of boron concentration in borosilicate glass, boron carbide and graphite samples by conventional wet-chemical and nuclear analytical methods

Journal of Radioanalytical and Nuclear Chemistry, 2014

Boron is an important element in nuclear technology. A comparative study was carried out for the ... more Boron is an important element in nuclear technology. A comparative study was carried out for the determination of boron in borosilicate glass, boron carbide and graphite samples by wet-chemical and nuclear analytical methods. Wet chemical methods namely titrimetry, Inductively Coupled Plasma Mass Spectrometry and ICP Optical Emission Spectrometry and nuclear analytical methods namely Particle Induced Gamma-Ray Emission and Nuclear Reaction Analysis were used. Boron concentrations were in trace (mg kg-1) level in graphite and percentage level in borosilicate glass and boron carbide.

Research paper thumbnail of Characterisation of graphite using boron as a marker element

AIP Conference Proceedings, 2013

Graphite has many industrial applications. Two of the most important applications are as electrod... more Graphite has many industrial applications. Two of the most important applications are as electrodes in industries and as moderator in nuclear industry. Determination of the Boron Equivalent of the impurity elements in graphite is the most important parameter for certifying the grade of graphite electrode [1]. The use of a suitable method with low limits of determination of boron is therefore necessary. A method has been standardised in Analytical Chemistry Division, BARC for determining trace amounts of boron in graphite electrodes. It involves controlled dissolution of graphite sample powder and measurement of boron by Inductively Coupled Plasma Mass Spectrometer (ICP-MS) using matrix matched standards. The method detection limit is 1 μg g−1. The method Relative Standard Deviation was 5%. The method was verified by spike recovery experiments. Recoveries were found to be within 100±2% in the concentration range of 1 to 100 μg g−1. The developed method has been adopted for the compositional characterizatio...

Research paper thumbnail of Characterization of As (V), As (III) by selective reduction/adsorption on palladium nanoparticles in environmental water samples

Talanta, 2009

Hydrazine (HZ) and sodium borohydride (BH) are commonly used reagents for the production of palla... more Hydrazine (HZ) and sodium borohydride (BH) are commonly used reagents for the production of palladium nanoparticles (PdNP) in aqueous solution and also for the reduction of arsenic from higher oxidation state to lower oxidation state. A methodology based on the quantitative adsorption of reduced arsenic species on PdNP generated in situ by BH and HZ is described to characterize As (V) and As (III) in environmental water samples. It was observed that PdNP obtained by BH gave quantitative recovery of As (V) and (III) and the PdNP obtained by HZ could account for As (III). The reduced palladium particles are collected and dissolved in minimum amount of nitric acid. The quantification of arsenic was carried out using GFAAS. Optimization of the experimental conditions and instrumental parameters were investigated in detail. The proposed procedure was validated by applying it for the determination of the content of total As in Certified Reference Material BND 301-02 (NPL, India). The detection limit of arsenic in environmental water samples was 0.029 g L −1 with an enrichment factor of 50. The relative standard deviation (R.S.D.) for 10 replicate measurements of 5 g mL −1 was 4.2%. The proposed method was successfully applied for the determination of sub ppm to ppm levels of arsenic (V), (III) in environmental water samples.

Research paper thumbnail of Forensic application of total reflection X-ray fluorescence spectrometry for elemental characterization of ink samples

Spectrochimica Acta Part B: Atomic Spectroscopy, 2010

The possibility of applying Total Reflection X-ray Fluorescence for qualitative and quantitative ... more The possibility of applying Total Reflection X-ray Fluorescence for qualitative and quantitative differentiation of documents printed with rare earth tagged and untagged inks has been explored in this paper. For qualitative differentiation, a very small amount of ink was loosened from the printed documents by smoothly rubbing with a new clean blade without destroying the manuscript. 50 μL of Milli-Q water was put on this loose powder, on the manuscript, and was agitated by sucking and releasing the suspension two to three times with the help of a micropipette. The resultant dispersion was deposited on quartz sample support for Total Reflection X-ray Fluorescence measurements. The Total Reflection X-ray Fluorescence spectrum of tagged and untagged inks could be clearly differentiated. In order to see the applicability of Total Reflection X-ray Fluorescence for quantitative determinations of rare earths and also to countercheck such determinations in ink samples, the amounts of rare earth in painted papers with single rare earth tagged inks were determined by digesting the painted paper in HNO 3 /HClO 4 , mixing this solution with the internal standard and recording their Total Reflection X-ray Fluorescence spectra after calibration of the instrument. The results thus obtained were compared with those obtained by Inductively Coupled Plasma Mass Spectrometry and were found in good agreement. The average precision of the Total Reflection X-ray Fluorescence determinations was 5.5% (1σ) and the average deviation of Total Reflection X-ray Fluorescence determined values with that of Inductively Coupled Plasma Mass Spectrometry was 7.3%. These studies have shown that Total Reflection X-ray Fluorescence offers a promising and potential application in forensic work of this nature.

Research paper thumbnail of A fluoride ion selective Zr(iv)-poly(acrylamide) magnetic composite

RSC Advances, 2014

ABSTRACT A fluoride ion selective magnetic sorbent has been synthesized by the encapsulation of F... more ABSTRACT A fluoride ion selective magnetic sorbent has been synthesized by the encapsulation of Fe3O4 nanoparticles in a network of Zr(IV) complexed poly(acrylamide) (Zr–PAM). This magnetic sorbent has been found to be efficient for the selective preconcentration of fluoride ions from natural waters. The Zr–PAM/Fe3O4 composite has been characterized using various physico-chemical techniques i.e. energy dispersive X-ray fluorescence (EDXRF), scanning electron microscopy (SEM), Fourier transform infra-red spectroscopy (FTIR) and a vibrating sample magnetometer (VSM). The Zr–PAM/Fe3O4 composite developed in the present work retains the super paramagnetic properties of Fe3O4 nanoparticles, and the results reveal that the sorption is rapid. The composite has a considerably higher fluoride sorption capacity (124.5 mg g-1) compared to other super-paramagnetic fluoride sorbents reported in the literature. Repeated sorption–regeneration cycles seem to suggest reusability of the sorbent for fluoride removal from natural waters, as well as other aqueous solutions having pH in the range 1–9.

Research paper thumbnail of Fusion method for sample preparation for isotopic composition determination of boron in refractory materials by thermal ionization mass spectrometry with validation using dissolved and purified samples

International Journal of Mass Spectrometry

Abstract Various refractory samples of boron such as titanium borides, rare earth borides, boron ... more Abstract Various refractory samples of boron such as titanium borides, rare earth borides, boron carbides having natural and non-natural isotopic composition were analysed by thermal ionization mass spectrometry as Na2BO2+ ions. Samples were fused with Na2CO3 directly on the filament after adjusting the B/Na mole ratio to 2 and in certain cases modifications in the loading technique were required to obtain precise 10B/11B isotopic ratio. A few of the samples expected to have natural 10B/11B ratio were observed to be slightly enriched in 10B. Dissolved samples as well as boron purified by extraction with 5% 2-Ethyl Hexane Diol(EHD) were analysed for 10B/11B ratio to ascertain the accuracy of the results obtained by the direct fusion method. Precision of about 0.02% (1RSD) was obtained for 10B/11B isotopic ratio measured in all the three types of samples. A good agreement of the dissolved sample and purified boron fraction with the directly fused sample validated the direct fusion method as a fast and reliable technique for isotopic analysis of boron in refractory samples.

Research paper thumbnail of Understanding the As(III) oxidative performance of MnO2 polymorphs (α, β, and γ) and synthesis of an efficient nanocomposite of iron ore slime derived 2-line ferrihydrite and γ-MnO2 for sequestration of total arsenic from aqueous solution

Chemical Engineering Journal, 2022

Research paper thumbnail of A Facile Strategy for Preparation of Yttrium-90 Therapeutic Sources for Radionuclide Therapy

Cancer Biotherapy and Radiopharmaceuticals, 2022

Background: Mold brachytherapy using high-energy b-emitting radioisotopes is a promising treatmen... more Background: Mold brachytherapy using high-energy b-emitting radioisotopes is a promising treatment modality for skin cancers and keloids. Simple methodologies for consistent and stable incorporation of radionuclides into the matrix are desired for preparation of therapeutic sources. Methods: The authors report a facile strategy for the stable incorporation of Yttrium-90 (90 Y) into amidoximefunctionalized polyacrylonitrile-polyvinylidene fluoride (PAN-PVDF) membranes. The strategy consisted of surface modification of PAN-PVDF membranes by reaction with hydroxylamine, characterization of the functionalized membranes, and optimization of experimental variables for maximum loading of 90 Y onto the membranes. Quality control tests essential for confirming the suitability of the 90 Y therapeutic sources for human application, such as uniformity of activity distribution, absence of leaching of activity, and estimation of surface contamination, were performed. Theoretical calculations to estimate the dose imparted by the 90 Y therapeutic sources at varying depths of tissue were also carried out to predict the possible therapeutic outcome of treatment. Results: A facile method for large-scale preparation of 90 Y-based mold brachytherapy sources could be established. Conclusions: The source fabrication methodology standardized in this work could be tailored for fabrication of custom-made 90 Y sources for individualized treatment of superficial tumors, Bowen's disease, and keloids.

Research paper thumbnail of Titanium dioxide, layered hydrazinium titanate and eggshell as potential sorbents for remediation of chromium from aqueous stream

Separation Science and Technology, 2020

Titanium dioxide (TiO 2), layered hydrazinium titanate (LHT) and eggshell were studied for sorpti... more Titanium dioxide (TiO 2), layered hydrazinium titanate (LHT) and eggshell were studied for sorption of chromium from aqueous streams. Among the three sorbents, the eggshell, a bio-waste is found to have maximum sorption capacity of 315 mg g −1. Sorption of Cr(III) as well as Cr(VI) was found to be spontaneous on LHT while TiO 2 and eggshell can accumulate only Cr(III). However, sorption of Cr(VI) on these was ensued after in situ reduction of Cr(VI) to Cr(III). Experimental result indicates absence of any interference from ions commonly present in ground water.

Research paper thumbnail of Quantitative Evaluation of 28 Mineral Elements by Inductively Coupled Plasma/Mass Spectrometry and Its Application in Source Identification of Indian Opium

Journal of AOAC INTERNATIONAL, 2005

An analytical method based on inductively coupled plasma/mass spectrometry (ICP/MS) was developed... more An analytical method based on inductively coupled plasma/mass spectrometry (ICP/MS) was developed for the determination of 28 mineral elements (Cr, Mn, Co, Ni, Cu, Zn, Ga, Sr, Cd, Ag, Ba, Pb, Bi Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) in Indian opium samples. The detection limits were found to be in the range of 0.0008–0.45 ng/mL. The recoveries of spiked samples for each element were found to be in the range of 83–106%, with a precision of less than 9%. A total of 124 opium samples from India were analyzed for the distribution pattern of the 28 mineral elements. Quantitative elemental data were subjected to chemometric analysis in order to determine an optimal classifier to evaluate the source of Indian opium. The study indicated that mineral elements might not be the suitable discriminators for the discrimination of licit opium-growing divisions of India. However, the methodology developed and the analytical data on elemental profile may find important foren...

Research paper thumbnail of Remediation of chromium(VI) ions as chromium oxide xerogel via gamma-radiolysis of aqueous waste discharge

Separation and Purification Technology, 2019

Remediation of chromium(VI) ions as chromium oxide xerogel via gamma-radiolysis of aqueous waste ... more Remediation of chromium(VI) ions as chromium oxide xerogel via gamma-radiolysis of aqueous waste discharge, Separation and Purification Technology (2019), doi:

Research paper thumbnail of Exploring Nanostructured Zr/Cu Composite Oxide (NZCO) as an Efficient Adsorbent for Removal of As(III) and As(V) from Aqueous Solution

ChemistrySelect, 2019

Consumption of arsenic contaminated water induces and aggravates major health problems in humans.... more Consumption of arsenic contaminated water induces and aggravates major health problems in humans. In this report, we have successfully synthesized nanostructured Zr/Cu composite oxide (NZCO) by ultrasonically assisted hydrothermal process for total arsenic sequestration. Various batch experiments were performed with NZCO to determine its adsorption efficacy for As(III) and As(V) species. NZCO demonstrated outstanding performance in removing arsenic species from water with maximum adsorption capacities of 72.25 mg g−1 and 107.5 mg g−1 for As (III) and As (V) respectively under optimized conditions. The adsorption kinetics was closely fitted to pseudo‐second order model and adsorption isotherms were well described by D−R isotherms model. Meanwhile, the adsorption tests performed on naturally occurring ground water samples confirmed the effectiveness of NZCO in remediating total arsenic level below the prescribed limit of WHO‐MCL (0.01 mg L−1). The adsorption mechanisms study exhibits ...

Research paper thumbnail of Corrosion behavior analyses of metallic membranes in hydrogen iodide environment for iodine-sulfur thermochemical cycle of hydrogen production

International Journal of Hydrogen Energy, 2018

Research paper thumbnail of Preparation of Radioactive Skin Patches Using Polyhydroxamic Acid-Grafted Cellulose Films Toward Applications in Treatment of Superficial Tumors

Cancer biotherapy & radiopharmaceuticals, 2017

The primary objective of this investigation is the development of a strategy for the synthesis of... more The primary objective of this investigation is the development of a strategy for the synthesis of polyhydroxamic acid (PHA)-grafted cellulose film, its characterization, and evaluation of its usefulness for the preparation of 177Lu skin patches for superficial brachytherapy applications. PHA-grafted cellulose films were synthesized and characterized by Fourier transformed infrared spectrometer analysis and visual color test with Fe(III) solution. Uptake of 177Lu on the PHA-grafted cellulose was investigated by varying the experimental conditions such as the pH of feed solution, amount of nonradioactive Lu carrier, time, and temperature of the reaction. Under the optimized conditions, >95% loading of 177Lu on the PHA-cellulose film could be achieved. Autoradiography studies of 177Lu-PHA-cellulose film confirmed the uniform distribution of 177Lu on the surface. Energy dispersive X-ray analysis of nonradioactive Lu-PHA-cellulose film confirmed the loading of Lu on PHA-cellulose film...

Research paper thumbnail of Optode sensor for on-site detection and quantification of hydroxide ions in highly concentrated alkali solutions

RSC Advances, 2015

Development of a colorimetric strip sensor for visual detection and quantification of hydroxide i... more Development of a colorimetric strip sensor for visual detection and quantification of hydroxide ions in highly concentrated alkali solutions.

Research paper thumbnail of Direct determination of uranium in seawater by laser fluorimetry

Talanta, 2008

A method for estimation of uranium in seawater by using steady state laser flourimetry is describ... more A method for estimation of uranium in seawater by using steady state laser flourimetry is described. Uranium present in seawater, in concentration of approximately 3 ng ml −1 was estimated without prior separation of matrix. Quenching effect of major ions (

Research paper thumbnail of Recovery and pre-concentration of uranium from secondary effluent using novel resin

International Journal of Nuclear Desalination, 2010

... 1, pp.28–36. Biographical notes: Sangita Pal joined BARC as Scientific Officer in 2006, after... more ... 1, pp.28–36. Biographical notes: Sangita Pal joined BARC as Scientific Officer in 2006, after completing PDF from HLRC. ... He was Chairman of International Nuclear Desalination Advisory Group (INDAG) of International Atomic Energy Agency (IAEA) for the term 2005–2008. ...

Research paper thumbnail of Development of a visual optode sensor for onsite determination of Hg(II)

Sensors and Actuators B: Chemical, 2015

A color changeable cellulose triacetate (CTA) membrane based optode has been developed for the hi... more A color changeable cellulose triacetate (CTA) membrane based optode has been developed for the highly selective and sensitive determination of Hg(II) ions in aqueous solutions. The sensing layer of the optode consists of phenylthiosemicarbazide derivative of rhodamine 6G immobilized in a plasticized cellulose triacetate membrane. The colorless optode film on reaction with Hg(II) turned pink in color and the intensity of the color was found to be directly proportional to the amount of Hg(II). The sensing mechanism is based on the mercury induced spirolactum ring opening followed by its cyclization to form highly conjugated system which leads to the development of pink color. Various experimental parameters such as pH, optode composition and response time have been optimized. Under these conditions the sensor showed a wide linear dynamic range of 10 to 5000 ng mL-1 Hg(II) with a detection limit of 1.3 ng mL-1. In addition to its stability and reproducibility, optode showed a high selectivity towards Hg(II) ions as compared to other co-existing ions in real water samples. The developed optode is suitable for rapid and on-site detection of Hg(II) ions in a variety of aqueous samples. The sensor was successfully applied for the determination of Hg(II) ions in ground water samples.

Research paper thumbnail of Functionalized polymer sheet sorbent for selective preconcentration and determination of mercury in natural waters

Anal. Methods, 2014

Mercury is considered as a highly toxic and widespread heavy-metal pollutant. In the present work... more Mercury is considered as a highly toxic and widespread heavy-metal pollutant. In the present work, two flat-sheet polymer sorbents have been synthesized for the selective preconcentration of mercury from natural waters. These are a silver nanoparticle (AgNP)-embedded poly(acrylamide)-grafted poly(propylene) sheet (Ag-PAM-PP) and a 1,8-octanedithiol-functionalized gold-coated poly(propylene) sheet (HS-octyl-S-Au-PP). The functional groups acrylamide and thiol provide the binding sites for Hg2+ ions; whereas silver nanoparticles reduce Hg2+ to Hg0 and it is held on the sheet by amalgam formation. Various factors that influence the preconcentration of Hg2+ from aqueous solution were investigated. Based on the comparison of the experimental results, it was observed that Ag-PAM-PP had superior performance for uptake of Hg2+ from natural water samples in terms of sorption capacity, sorption kinetics and working pH range. The uptake of Hg2+was found to be pH dependent with a maximum of 95% at pH 7.5. The preconcentration of Hg2+ from a large volume of aqueous solution was used to extend the lower limit of the concentration range that can be quantified by EDXRF and CV-AAS. The sorbed Hg(II) from aqueous samples was quantitatively detected within 1 min using EDXRF. The LOD (3σ) for CV-AAS (RSD = 2%) and EDXRF (RSD = 5%) were 6 and 30 μg L−1, respectively. The method was applied for the determination of Hg2+ in groundwater and seawater samples in the presence of a high concentration of interfering ions.

Research paper thumbnail of A visual strip sensor for determination of iron

Analytica Chimica Acta, 2014

A visual strip sensor for on-site detection of iron has been developed and made. The sensor is ea... more A visual strip sensor for on-site detection of iron has been developed and made. The sensor is easy to synthesize, portable and recyclable with shelf life >1 year. Visual detection limit for iron using the present sensor is 50 ng mL À1. Visual strip sensor was applied to ground water and fruit juices.

Research paper thumbnail of Determination of boron concentration in borosilicate glass, boron carbide and graphite samples by conventional wet-chemical and nuclear analytical methods

Journal of Radioanalytical and Nuclear Chemistry, 2014

Boron is an important element in nuclear technology. A comparative study was carried out for the ... more Boron is an important element in nuclear technology. A comparative study was carried out for the determination of boron in borosilicate glass, boron carbide and graphite samples by wet-chemical and nuclear analytical methods. Wet chemical methods namely titrimetry, Inductively Coupled Plasma Mass Spectrometry and ICP Optical Emission Spectrometry and nuclear analytical methods namely Particle Induced Gamma-Ray Emission and Nuclear Reaction Analysis were used. Boron concentrations were in trace (mg kg-1) level in graphite and percentage level in borosilicate glass and boron carbide.

Research paper thumbnail of Characterisation of graphite using boron as a marker element

AIP Conference Proceedings, 2013

Graphite has many industrial applications. Two of the most important applications are as electrod... more Graphite has many industrial applications. Two of the most important applications are as electrodes in industries and as moderator in nuclear industry. Determination of the Boron Equivalent of the impurity elements in graphite is the most important parameter for certifying the grade of graphite electrode [1]. The use of a suitable method with low limits of determination of boron is therefore necessary. A method has been standardised in Analytical Chemistry Division, BARC for determining trace amounts of boron in graphite electrodes. It involves controlled dissolution of graphite sample powder and measurement of boron by Inductively Coupled Plasma Mass Spectrometer (ICP-MS) using matrix matched standards. The method detection limit is 1 μg g−1. The method Relative Standard Deviation was 5%. The method was verified by spike recovery experiments. Recoveries were found to be within 100±2% in the concentration range of 1 to 100 μg g−1. The developed method has been adopted for the compositional characterizatio...

Research paper thumbnail of Characterization of As (V), As (III) by selective reduction/adsorption on palladium nanoparticles in environmental water samples

Talanta, 2009

Hydrazine (HZ) and sodium borohydride (BH) are commonly used reagents for the production of palla... more Hydrazine (HZ) and sodium borohydride (BH) are commonly used reagents for the production of palladium nanoparticles (PdNP) in aqueous solution and also for the reduction of arsenic from higher oxidation state to lower oxidation state. A methodology based on the quantitative adsorption of reduced arsenic species on PdNP generated in situ by BH and HZ is described to characterize As (V) and As (III) in environmental water samples. It was observed that PdNP obtained by BH gave quantitative recovery of As (V) and (III) and the PdNP obtained by HZ could account for As (III). The reduced palladium particles are collected and dissolved in minimum amount of nitric acid. The quantification of arsenic was carried out using GFAAS. Optimization of the experimental conditions and instrumental parameters were investigated in detail. The proposed procedure was validated by applying it for the determination of the content of total As in Certified Reference Material BND 301-02 (NPL, India). The detection limit of arsenic in environmental water samples was 0.029 g L −1 with an enrichment factor of 50. The relative standard deviation (R.S.D.) for 10 replicate measurements of 5 g mL −1 was 4.2%. The proposed method was successfully applied for the determination of sub ppm to ppm levels of arsenic (V), (III) in environmental water samples.

Research paper thumbnail of Forensic application of total reflection X-ray fluorescence spectrometry for elemental characterization of ink samples

Spectrochimica Acta Part B: Atomic Spectroscopy, 2010

The possibility of applying Total Reflection X-ray Fluorescence for qualitative and quantitative ... more The possibility of applying Total Reflection X-ray Fluorescence for qualitative and quantitative differentiation of documents printed with rare earth tagged and untagged inks has been explored in this paper. For qualitative differentiation, a very small amount of ink was loosened from the printed documents by smoothly rubbing with a new clean blade without destroying the manuscript. 50 μL of Milli-Q water was put on this loose powder, on the manuscript, and was agitated by sucking and releasing the suspension two to three times with the help of a micropipette. The resultant dispersion was deposited on quartz sample support for Total Reflection X-ray Fluorescence measurements. The Total Reflection X-ray Fluorescence spectrum of tagged and untagged inks could be clearly differentiated. In order to see the applicability of Total Reflection X-ray Fluorescence for quantitative determinations of rare earths and also to countercheck such determinations in ink samples, the amounts of rare earth in painted papers with single rare earth tagged inks were determined by digesting the painted paper in HNO 3 /HClO 4 , mixing this solution with the internal standard and recording their Total Reflection X-ray Fluorescence spectra after calibration of the instrument. The results thus obtained were compared with those obtained by Inductively Coupled Plasma Mass Spectrometry and were found in good agreement. The average precision of the Total Reflection X-ray Fluorescence determinations was 5.5% (1σ) and the average deviation of Total Reflection X-ray Fluorescence determined values with that of Inductively Coupled Plasma Mass Spectrometry was 7.3%. These studies have shown that Total Reflection X-ray Fluorescence offers a promising and potential application in forensic work of this nature.