SANGITA DAS
@durham.ac.uk
Royal Society Newton International Fellow, UK in Department of Chemistry Durham University
Durham University, UK
RESEARCH INTERESTS
1.Synthesis and characterization of fluorescence Probe (Detection of Metal Ions, Anions, Reactive Oxygen Species, Nerve Gas and Other Environmentally Hazardous Species etc.)
2.Aggregation Induced Emission Dyes and Solid State Emitters
3.Synthesis of compounds with anti-diabetic activity
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Bibaswan Sen, Sayantani Paul, Pawel̷ Krukowski, Debojyoti Kundu, Sangita Das, Priyabrata Banerjee, Magdalena Mal̷ecka, Sk Jahir Abbas, and Sk Imran Ali
American Chemical Society (ACS)
CuAs2O4 has been explored as a heterogeneous catalyst in the fields of photocatalysis, electrocatalysis, and solvent-free organic transformation reactions. The homogeneity has been successfully attained for the first time by designing a pH-assisted hydrothermal synthesis technique. Single-crystal X-ray diffraction studies reveal that no phase transition has been observed by lowering the temperature up to 103 K with no existence of satellite reflections. The crystal structure exhibits tetragonal symmetry with space group P42/mbc and consists of [CuO6] octahedra and [AsO3E] tetrahedra (E represents the stereochemically active lone pair). Structural investigation shows a cylindrical void inside the structure, which could lead to interesting physical and chemical properties. The photocatalytic dye degradation efficiency with methylene blue (MB) showed ∼100% degradation, though the degradation efficiency increased by 2-fold with the addition of 6% H2O2. The reusability of the catalyst up to the 10th cycle with ∼35% MB dye degradation has been established. It can exhibit HER activity with a low overpotential of 165 mV with respect to RHE to attain the current density of j = 10 mA cm-2. SEM and TEM revealed rod-shaped particles, which supported the large number of catalytic active sites. The structural consistency of the catalyst after photodegradation and HER studies is confirmed by the PXRD pattern. XPS confirms the oxidation state of Cu and As in the compound. The catalytic activity toward the Knoevenagel condensation reaction at moderate temperature under solvent-free condition is also studied. TG-DTA shows an endothermic minimum (Tmin) at 436 °C due to the mass loss of As2O3.
Sangita Das, Sayantani Paul, Bibaswan Sen, Pratyasha Rudra, Swastik Mondal, and Sk Imran Ali
American Chemical Society (ACS)
A potential adsorbent, Sb4O5Cl2@NbSe2 composite, was generated from the Sb4O5Cl2 photocatalyst and 5 wt % layered 2H-NbSe2 nanoparticles for the highly effective removal of Cr(VI) and Fe(III) ions and methyl orange (MO) from aqueous solution, and a comparison was drawn against the precursors. Sb4O5Cl2 crystallites and NbSe2 nanoparticles were synthesized hydrothermally, and the composite was prepared by the incipient wetness impregnation technique. The crystal structure of Sb4O5Cl2 was determined by single-crystal X-ray diffraction (SCXRD) data. Powder X-ray diffraction (PXRD) study revealed the 2H phase of NbSe2 nanoparticles. Field emission scanning electron microscopy (FESEM) analysis confirmed the formation of the spherical-shaped NbSe2 nanoparticles from rod-shaped bulk 2H-NbSe2. Morphological changes from the hexagonal to irregular prismatic shape were found upon the formation of the Sb4O5Cl2@NbSe2 composite compared to pure Sb4O5Cl2. Negative ζ-potential values indicated that electrostatic interactions were the predominant factor for the adsorption process. Sb4O5Cl2@NbSe2 provided removal efficiencies of 99% for MO in 6 h, 96.52% for Cr(VI) within 2.5 h, and 92.43% for Fe(III) within 4 h of 10 mg/L initial concentration. The maximum adsorption capacities of the composite for MO, Fe(III), and Cr(VI) were found to be 66.56, 131.48, and 122.30 mg/g, respectively, as calculated using the Langmuir isotherm equation.
Sayantani Paul, Sangita Das, Nayim Sepay, Bibaswan Sen, and Sk Imran Ali
American Chemical Society (ACS)
Sangita Das, Partha Pratim Das, and Sabu Thomas
Wiley
Sangita Das, Sayantani Paul, Bibaswan Sen, Siriyara J. Prathapa, Sk Jahir Abbas, Asoke P. Chattopadhyay, and Sk Imran Ali
American Chemical Society (ACS)
Sangita Das, Partha Pratim Das, James W. Walton, Ching Kheng Quah, Kakali Ghoshal, and Maitree Bhattacharyya
Elsevier BV
Bibaswan Sen, Sayantani Paul, Sangita Das, Asoke P. Chattopadhyay, and Sk Imran Ali
Elsevier BV
Sayantani Paul, Bibaswan Sen, Nilendu Basak, Nirman Chakraborty, Kiron Bhakat, Sangita Das, Ekramul Islam, Swastik Mondal, Sk Jahir Abbas, and Sk Imran Ali
American Chemical Society (ACS)
Zn3Sb4O6F6 crystallites were synthesized by a pH-regulated hydrothermal synthetic approach, while doping on Zn3Sb4O6F6 by KI was performed by the "incipient wetness impregnation technique." The effect of KI in Zn3Sb4O6F6 is found with the changes in morphology in the doped compound, i.e., needle-shaped particles with respect to the irregular cuboid and granular shaped in the pure compound. Closer inspection of the powder diffraction pattern of doped compounds also reveals the shifting of Braggs' peaks toward a lower angle and the difference in cell parameters compared to the pure compound. Both metal oxyfluoride comprising lone pair elements and their doped compounds have been successfully applied as photocatalysts for methylene blue dye degradation. Knoevenagel condensation reactions were performed using Zn3Sb4O6F6 as the catalyst and confirmed 99% yield even at 60 °C temperature under solvent-free conditions. Both pure and KI-doped compounds were tested against several standard bacterial strains, i.e., Enterobacter sp., Escherichia coli, Staphylococcus sp., Salmonella sp., Bacillus sp., Proteous sp., Pseudomonas sp., and Klebsiella sp. by the "disk diffusion method" and their antimicrobial activities were confirmed.
Sayantani Paul, Bibaswan Sen, Sangita Das, Sk Jahir Abbas, Surya Narayan Pradhan, Kakali Sen, and Sk Imran Ali
Informa UK Limited
ABSTRACT Bioplastics are used as potent eco-friendly alternatives to minimise the adverse environmental impacts induced by petroleum-based plastics. Bioplastics, especially biodegradable plastics are materials that can be produced from non-edible or waste products of agricultural fields and kitchens and could be decomposed by the microorganisms at the end conventional plastics are mainly mineral oil-based which mitigate one of the important resources of humanity. Though petrochemical-based plastics are very important materials in our daily lives, but excessive use and our negligence create severe plastic pollution. Due to the lack of proper handling of plastic wastes, they are piled up on soil day by day and cause environmental pollution. These waste substances pollute the soil by releasing harmful chemicals. Accumulation of plastic wastes especially thin polyethylene bags clog the drainage systems or dumps causing overflow of it or even flooding. Each year trillions of plastic residues are being released into the ocean. Such petrochemical plastic wastes like tiny pellets, crackers discharge nasty toxic chemicals which endanger the life of aquatic animals. In some cases, the petrochemical wastes have been burned which release toxic gasses and they combine with the water vapour present in the air, which may create acid rain. Post-invasion into the biosphere, microplastics may cause adverse health effects upon living organisms. On the contrary, bioplastics have the ability to minimise these harmful issues and henceforth become one of the interesting topics in the twenty-first century. Bioplastics, such as PLA, PHA, PHB, PHV, PHH, and starch polymers and their modified form by tuning physical and chemical properties will show the new dimension in many applications to overcome and replacing many synthetic plastics. The present work reviewed how bio-derived plastics achieve such interest and how it becomes the most acceptable substitute to beat this venomous plastic pollution.
Sangita Das, Lakshman Patra, Partha Pratim Das, Kakali Ghoshal, Saswati Gharami, James W. Walton, Maitree Bhattacharyya, and Tapan Kumar Mondal
Royal Society of Chemistry (RSC)
A new ratiometric fluorescent probe (E)-2-(benzo[d]thiazol-2-yl)-3-(8-methoxyquinolin-2-yl)acrylonitrile (HQCN) was synthesised by the perfect blending of quinoline and a 2-benzothiazoleacetonitrile unit. The probe can selectively detects hydrazine and hypochlorite with two different outputs.
Sangita Das, Partha Pratim Das, James. W. Walton, Kakali Ghoshal, Lakshman Patra, and Maitree Bhattacharyya
Royal Society of Chemistry (RSC)
Detection of biological phosphate is very important for environmental and health care applications.
Partha Pratim Das, Sudeshna Samanta, Sangita Das, Ratnadwip Singha, Thomas Vogt, and Yongjae Lee
American Chemical Society (ACS)
Sayantani Paul, Bibaswan Sen, Nirman Chakraborty, Sangita Das, Swastik Mondal, Asoke P. Chattopadhyay, and Sk Imran Ali
Royal Society of Chemistry (RSC)
A pH-regulated hydrothermal synthesis method was employed to synthesize Sb4O5Br2 and Sb4O5Cl2 crystallites.
Sangita Das, Partha Pratim Das, James W. Walton, Kakali Ghoshal, Lakshman Patra, Maitree Bhattacharyya, Tapan Kumar Mondal, and Sabu Thomas
Elsevier BV
Sangita Das, Partha Pratim Das, and Sabu Thomas
Elsevier
Sangita Das, Partha Pratim Das, James W. Walton, Kakali Ghoshal, Lakshman Patra, and Maitree Bhattacharyya
Royal Society of Chemistry (RSC)
FRET based ratiometric switch for selective sensing of Al3+ with bio-imaging in human peripheral blood mononuclear cells (PBMCs).
Lakshman Patra, Paramita Ghosh, Sangita Das, Saswati Gharami, Nabendu Murmu, and Tapan Kumar Mondal
Elsevier BV
Abstract Herein, we have designed and synthesized an effective fluorogenic chemosensor, BTCP for the sensing of DCP, a very low toxic simulant of sarin both in the vapour and solution phases. The poor emission property (λmax = 470 nm, quantum yield (φ) = 0.051) of BTCP is significantly increased in the presence of DCP with a red shift of the emission wavelength (λmax = 542 nm, quantum yield (φ) = 0.241) in CH3CN/H2O (1/1, v/v, pH = 7.2) medium. The limit of detection is found to be as low as 15.8 nM for the detection of DCP. Moreover, the fluorescent probe (BTCP) is very useful for the visualization of DCP within human lung cancer cell lines (A549). Sensing of the probe is based on the formation of a new adduct, BTCP-DCP and inhibition of photo-induced electron transfer (PET) process present in the free BTCP. The structure of the probe (BTCP) is confirmed by single crystal X-ray crystallography. Density functional theory (DFT) and time dependent density functional theory (TDDFT) computational techniques are used to interpret the electronic structure and Uv–vis spectra of both BTCP and BTCP-DCP adduct.
Krishnendu Aich, Sangita Das, Saswati Gharami, Lakshman Patra, and Tapan Kumar Mondal
Wiley
Saswati Gharami, Krishnendu Aich, Sangita Das, Lakshman Patra, and Tapan Kumar Mondal
Royal Society of Chemistry (RSC)
Here a new quinoline-based (BIMQ) probe was developed which displayed ratiometric detection of organophosphorus chemical vapor threat, DCP.
Sangita Das, Krishnendu Aich, Lakshman Patra, Kakali Ghoshal, Saswati Gharami, Maitree Bhattacharyya, and Tapan Kumar Mondal
Elsevier BV
Abstract Increased oxidative stress in metabolic complications like type 2 diabetes, dyslipidemia and cardiovascular disorders exerts potential health hazards in many facets. Enhanced production of reactive oxygen species (ROS) due to increased oxidative stress promotes the damage of many biologically important macromolecules. Hypochlorous acid (HOCl), a microbicidal agent is also known to be an important ROS sub-species. An enhanced generation of endogenous HOCl due to diseased condition therefore can be detrimental to health. In present work, a new quinoline-diaminomaleonitrile based probe (HQMN) has been designed for the selective detection of hypochlorite. The probe in hand shows a selective ratiometric emission change towards OCl − . The probe behaves as a highly selective and sensitive tool for the detection of OCl − over other analytes with a fast response time (within 100 s). Bioimaging study revealed that HQMN can detect endogenous OCl − in human monocytes and an increase in endogenous HOCl concentration has been witnessed in diabetic condition compared to healthy control. Thus HQMN can be used as an excellent fluorescent probe for dynamic tracking of hypochorite in living biological cells especially to identify diabetic conditions.
Lakshman Patra, Sangita Das, Saswati Gharami, Krishnendu Aich, and Tapan Kumar Mondal
Royal Society of Chemistry (RSC)
The synthesized ESIPT based fluorogenic chemosensor, H2L, selectively detects Zn2+and Al3+in a MeOH–H2O (4/1, v/v, pH = 7.2) medium.