Browsing by Author "Ankur Srivastava"

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A highly efficient nanostructured Au@La2O3 based platform for dopamine detection
(Elsevier B.V., 2022) Ankur Srivastava; Gargi Mishra; Jay Singh; Mrituanjay D. Pandey
In the present work, nanostructured La2O3 and Au doped La2O3 nanocomposites were prepared hydrothermally that were further deposited electrophoretically onto the indium-tin-oxide (ITO) glass surface. The tyrosinase enzyme (Tyr) have been immobilized on the AuNPs modified La2O3/ITO electrode. The fabricated electrode Tyr/Au-La2O3/ITO was utilized for the determination of dopamine. The structural and morphological characterization were done by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Atomic force microscopy (AFM), Transmission electron microscopy (TEM & HR-TEM) and Energy dispersive X-ray analysis (EDX). The results of electrochemical response studies of fabricated electrode Tyr/Au-La2O3/ITO exhibit a linear range of 2–100 µm, sensitivity 2.4806 × 10−7 A/μM and limit of detection of 0.258 μM with response time 30 s and good reproducibility. The fabricated electrode might provide an efficient biointerface for the application of the rare earth metal oxide nanomaterials in biosensors and bioelectronics. © 2021 Elsevier B.V.
Advancements in the development of fluorescent chemosensors based on C=N bond isomerization/modulation mechanistic approaches
(Royal Society of Chemistry, 2024) Arpna Tamrakar; Manzoor Ahmad Wani; Gargi Mishra; Ankur Srivastava; Rampal Pandey; Mrituanjay D. Pandey
The C N bond isomerization/modulation as a fluorescence signalling mechanism was explored by studying the photophysical properties of conformationally restricted molecules. From the beginning, the C N bond isomerization method has attracted the attention of researchers owing to its simplicity, high selectivity, and sensitivity in fluorescence evaluation. Continuous developments in the field of sensing using C N bond-containing compounds have been achieved via the customization of the isomerization process around the C N bond in numerous ways, and the results were obtained in the form of specific discrete photophysical changes. C N isomerization causes significant fluorescence enhancement in response to detected metal cations and other reactive species (Cys, Hys, ClO−, etc.) straightforwardly and effectively. This review sheds light on the process of C N bond isomerization/modulation as a signalling mechanism depending on fluorescence changes via conformational restriction. In addition, C N bond isomerization-based fluorescent sensors have yet to be well reviewed, although several fluorescent sensors based on this signalling mechanism have been reported. Therefore, C N-based fluorescent sensors are summarized in this review. © 2024 The Royal Society of Chemistry.
Aloe vera gel (Aloe barbadensis miller) derived self-assembled flower-shaped carbon quantum dot interface for ultra-sensitive electrochemical detection of the endocrine disruptor bisphenol-A
(Royal Society of Chemistry, 2024) Ankur Srivastava; Kshitij RB Singh; Khrsheed Ahmed; Ravindra Pratap Singh; Mrituanjay D. Pandey; Shyam S. Pandey; Jay Singh
This manuscript is focused on the synthesis of biologically derived carbon quantum dots (CQDs) via hydrothermal methods using Aloevera leaves (Aloe barbadensis miller). The proposed biochemical route, utilizing Aloevera gel, has garnered attention due to its cost-effectiveness, eco-friendly nature, and ability to produce highly pure, stable, and fluorescent biologically derived self-assembled nanoparticles measuring approximately 5-6 nm in size. The primary objective was to harness plant sources and establish a sustainable and renewable platform for synthesizing valuable nanostructures, encouraging researchers to shift their focus from unhealthy chemicals to natural resources for healthier and non-polluting investigations. The synthesized CQDs exhibited remarkable colloidal properties, excellent fluorescence, and photostability under UV light. Characterization techniques such as powder XRD, UV-Vis spectroscopy, photoluminescence, FT-IR, AFM, and TEM were employed to analyse the prepared CQDs. Furthermore, the prepared CQDs displayed significant electrochemical behaviour in the presence of tyrosinase enzyme to detect Bisphenol-A, which functions as an endocrine disruptor (ED). These nanomaterials were also utilized for electrochemical biosensing applications. Additionally, the fabricated CQDs exhibited unique structural and morphological characteristics, along with efficient electrochemical properties, which are thoroughly discussed in the manuscript. © 2024 The Royal Society of Chemistry
Carbonaceous Catalysts for Pollutant Degradation
(wiley, 2023) Poonam Kaswan; Santimoy Khilari; Ankur Srivastava; Girijesh Kumar; Pratap K. Chhotaray; Mrituanjay D. Pandey; Kamalakanta Behera
To enhance the quality of the environment, a lot of studies have been done on carbonaceous materials to develop different architectures and qualities. The development and importance of carbonaceous photocatalysts is briefly highlighted in this chapter, which also includes different semiconductors based on activated carbon, carbon nanotubes, carbon dots, fullerene, graphene, aerogels and carbon sponges, etc. In the present chapter, we have considered two types of strategies to discuss the entitled topic, one is a carbon-based catalyst, and the second is carbonaceous material with other metal composites to enhance the activity. Various difficulties with a metal catalyst, such as limited light adsorption capacity, large band gap energy, and insufficient physicochemical stability, continue to severely restrict photocatalysts for practical uses. To get rid of this, some unique catalysts based on carbon materials have been designed and inserted into a photocatalytic system to enhance activity. They are found to be ideal for various types of applications ranging from the field of renewable energy to waste water management and treatment, thanks to the synergistic combination of metal nanoparticles and carbonaceous nanostructures. Carbon-based metal nanostructures are much essential to dissolve a variety of colorful and colorless hazardous contaminants, such as organic dye, NOXelimination, water splitting, etc., when they are subjected to visible light. © 2023 Scrivener Publishing LLC.
Efficient removal of chromate from wastewater using a one-pot synthesis of chitosan cross-linked ceria incorporated hydrous copper oxide bio-polymeric composite
(Elsevier B.V., 2024) Ayan Ghosh; Sumana Mondal; Sarat Kanrar; Ankur Srivastava; Mrituanjay D. Pandey; Uday Chand Ghosh; Palani Sasikumar
Remediating hexavalent chromium [Cr(VI)] from contaminated water systems is a significant concern due to its harmful effects on human health, aquatic life, and plants. To tackle this issue, scientists have created a chitosan cross-linked hydrous ceria incorporated cupric oxide bio-polymeric composite (CHCCO) by combining chitosan biopolymer with corresponding metal ions using glutaraldehyde as a cross-linker. The composite was characterized using advanced analytical instruments such as FTIR, p-XRD, SEM, XPS, etc. The synthesized composite (CHCCO) was then tested for its efficiency in removing Cr(VI) from synthetic Cr(VI) aqueous samples. The parameters examined included pH, material dose, contact time, concentration, temperature, and co-existing ions. The experimental data showed that the kinetics and equilibrium data fit well with the pseudo-second-order and the Freundlich isotherm models, respectively. Thermodynamic analysis demonstrated that the investigated surface adsorption process is spontaneous and endothermic. Except for the SO42− ion, no other species imparts adverse influence significantly on the reaction. The CHCCO bio-composite surfaces were refreshed using a dilute NaOH (1.0 M) solution and effectively recycled five times for Cr(VI) adsorption, indicating no significant surface activity deterioration. This study highlights the high effectiveness of CHCCO bio-polymeric composites in Cr(VI) remediation and the potential for this technology as an easy-to-use technique for environmental restoration. © 2024 Elsevier B.V.
Electronic metal-organic framework sensors
(wiley, 2023) Ankur Srivastava; Rahul Verma; Gargi Mishra; Jay Singh; Mrituanjay D. Pandey
Metal-organic frameworks (MOFs) are well-ordered and managed inorganic and organic molecules or complexes with large surface area and also the porosity. The size and shape is tunnel-like, having host-guest relations causes both physical and chemical sensitivity, such as temperature, pressure, pH, and light. These are active materials in device manufacturing, such as radiation detectors, chemical sensors, photodetectors, and various more. Electronic area and sensor devices are the new generations' research challenges. The hybrid creations in MOFs are also a new working field these days. In the present book chapter, we sum up the basic principle, and current literature on MOFs-based electronic sensors, such as optical, chemiresistive, and electromechanical sensors in terms of work function of MOFs, futures challenges, as well as prospects outlook. © 2024 WILEY-VCH GmbH. Published 2024 by WILEY-VCH GmbH. All rights reserved.
Evaluation of Spatio-Temporal Evapotranspiration Using Satellite-Based Approach and Lysimeter in the Agriculture Dominated Catchment
(Springer, 2021) Utkarsh Kumar; Ankur Srivastava; Nikul Kumari; Rashmi; Bhabagrahi Sahoo; Chandranath Chatterjee; Narendra Singh Raghuwanshi
Crop coefficient (Kc) represents the actual crop growth of the crop. It plays an important role in estimating water requirements at the different growth stages of the crop. However, FAO 56 Penman–Monteith Kc method does not account for spatial heterogeneity and uncertainty for regional climatic conditions significantly. Therefore, this study aims to develop the relation between Kc and normalized difference vegetation index (NDVI) using a linear regression and back calculations. These relationships were adjusted to local conditions using information from survey data obtained during Rabi season (2014–2015). The NDVI–Kc model (r2 = 0.86) has developed using NDVI–Kc from a fine resolution Landsat 8 remote sensing data. NDVI–Kc regression equation was utilized for generating crop coefficient for different month of season. The Vegetation Index-based AET estimated was evaluated with lysimeter data for different crop growth stage across the season. The results have shown that NDVI–Kc estimated AET has been better correlated with NDVI–Kc remote sensing model. Thus, the output of this research can help to calculate actual water demand in a command area and be helpful in allocating water from less demand area toward more demand area. © 2021, Indian Society of Remote Sensing.
Evaluation of Standardized MODIS-Terra Satellite-Derived Evapotranspiration Using Genetic Algorithm for Better Field Applicability in a Tropical River Basin
(Springer, 2023) Utkarsh Kumar; Rashmi; Ankur Srivastava; Nikul Kumari; Chandranath Chatterjee; Narendra Singh Raghuwanshi
Evapotranspiration (ET) estimation at different spatial and temporal scales with a paucity of climatic parameters in a river basin is becoming a challenging task. Accurate estimation of ET is necessary for efficient water resource management and improving water efficiency at the field scale. Therefore, this study attempts to indirectly estimate actual ET from version 006 of MODIS-Terra product (MOD16A2.006), Sentinel-2A and Variable infiltration capacity (VIC-3L) model using survey information collected from a traditional paddy field in Kangsabati river basin. Further, this study is undertaken to standardize raw MODIS-Terra ET product (MOD16A2.06) using a genetic-based algorithm for better field applicability at local condition. The MODIS-standardized ET and ET estimated using different methods along with raw MODIS-Terra ET product were evaluated against observed ET estimated using globally recommended FAO-56 Penman–Monteith (PM) equation coupled with a crop coefficient. MODIS-Terra ET estimates were standardized using a genetic-based algorithm to enhance the efficacy of MODIS-Terra ET (MODIS-raw ET) for better field applicability. The result revealed that the genetic-based algorithm (MODIS-standardized ET) improved significantly with the NSE and RMSE from approximately − 0.03 to 0.86 and 13.89 to 2.56 (mm/8 day). Of various ET models Sentinel-2A ET performed best followed by MODIS-standardized ET, VIC-3L ET and MODIS-raw ET with R2 = 0.92, NSE = 0.89, RMSE = 1.89 (mm/8 day), R2 = 0.88, NSE = 0.86, RMSE = 2.47 (mm/8 day), R2 = 0.77, NSE = 0.76, RMSE = 3.02 (mm/8 day) and R2 = 0.41, NSE = − 0.03, RMSE = 7.31 (mm/8 day), respectively. The result showed that Sentinel 2A and MODIS-standardized-based ET can be used under data scarce conditions for better field applicability and water management practices. © 2023, Indian Society of Remote Sensing.
Gemini surfactant-stabilized Pd nanoparticles: Synthesis, characterization, and catalytic application in the reduction and reductive acetylation in the water solvent
(John Wiley and Sons Ltd, 2023) Pranshu K. Gupta; Ankur Srivastava; Kalluri V.S. Ranganath
A series of Gemini surfactants (GSs) were prepared by reacting alkyl bromides with N,N,N′,N′-tetramethyl ethylenediamine. Various alkyl bromides used in for the preparation of GSs are 1,3-dibromo ethane, 1,3-dibromoethane, 1-Bromohexane, 1-Bromooctane, 1-Bromooctadecane and 1-Bromooctadodecane. Different solvents and temperatures were investigated for the formation of gels of prepared GSs. Among all, 1-Bromooctane, 1-Bromooctadecane-derived GSs formed organogels. Thus, synthesized long-chain organogels have been used to stabilize Pd NPs. The Pd NPs formation initially confirmed through Ultraviolet-visible, Scanning Electron Microscopy, and Atomic Force Micrograph studies. Later Fourier Tansform Infra Red, Thermo Gravimetric Analysis, and Zeta potential studies were also carried out to understand their properties extensively. The Pd NPs stabilized by GSs have been identified as a potential catalyst in the reductive N-acetylation of nitroaromatics at room temperature. The N-acetylated products were obtained in good yields in an aqueous medium. In addition, the potentiality of our catalyst has been also evaluated in the reduction of nitroaromatics in an aqueous medium, which is a green protocol. Further, the semi-empirical geometry optimizations of active GS gel confirmed the dihedral angle of 59° in between the two octyl moieties calculated from computational studies. The rheological properties such as amplitude sweeping, viscosity shear profile of the gel have also been studied. © 2023 John Wiley & Sons Ltd.
Groundwater quality issues and challenges for drinking and irrigation uses in central ganga basin dominated with rice-wheat cropping system
(MDPI, 2021) Sumant Kumar; Manish Kumar; Veerendra Kumar Chandola; Vinod Kumar; Ravi K. Saini; Neeraj Pant; Nikul Kumari; Ankur Srivastava; Surjeet Singh; Rajesh Singh; Gopal Krishan; Shashi Poonam Induwar; Sudhir Kumar; Brijesh Kumar Yadav; Nityanand Singh Maurya; Anju Chaudhary
Increased population and increasing demands for food in the Indo-Gangetic plain are likely to exert pressure on fresh water due to rise in demand for drinking and irrigation water. The study focuses on Bhojpur district, Bihar located in the central Ganga basin, to assess the groundwater quality for drinking and irrigation purpose and discuss the issues and challenges. Groundwater is mostly utilized in the study area for drinking and irrigation purposes (major crops sown in the area are rice and wheat). There were around 45 groundwater samples collected across the study region in the pre-monsoon season (year 2019). The chemical analytical results show that Ca2+, Mg2+ and HCO3− ions are present in abundance in groundwater and governing the groundwater chemistry. Further analysis shows that 66%, 69% and 84% of the samples exceeded the acceptable limit of arsenic (As), Fe and Mn respectively and other trace metals (Cu, Zn, Pb, Cd) are within the permissible limit of drinking water as prescribed by Bureau of Indian Standard for drinking water. Generally, high as concentration has been found in the aquifer (depth ranges from 20 to 40 m below ground surface) located in proximity of river Ganga. For assessing the irrigation water quality, sodium adsorption ratio (SAR) values, residual sodium carbonate (RSC), Na%, permeability index (PI) and calcium alteration index (CAI) were calculated and found that almost all the samples are found to be in good to excellent category for irrigation purposes. The groundwater facie has been classified into Ca-Mg-HCO3 type. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Hexavalent chromium scavenging performances of one-pot synthesized hydrous cerium-copper-mixed oxide from contaminated water with plausible mechanism
(Taylor and Francis Ltd., 2024) Ayan Ghosh; Sarat Kanrar; Ankur Srivastava; Mrituanjay D. Pandey; Uday Chand Ghosh; Palani Sasikumar
Prolonged use of the chromate [Cr(VI)]-contaminated water originates severe health problems for the public. Thus, the societal urgency is a reusable and cost-effective material for efficient scavenging of Cr(VI) from contaminated industrial wastewater. Aiming this, we had targeted to prepare some cheap and effective materials for scavenging Cr(VI) from the contaminated water. Herein, we report the preparation of hydrous cerium-copper oxide (HCCO) with some tailored compositions and employed toward the abstraction of chromate from water solution. The HCCO (Ce: Cu = 1:4, mole/mole) has shown the highest Cr(VI) scavenging capacity. Experimentally, highest Cr(VI) abstraction efficiency is recorded at pH ~ 3.0 (508.853 mg. g−1 at 303 K). Kinetically, the Cr(VI) scavenging reaction with HCCO surfaces agrees better with the pseudo second-order model (R2 = 0.987) equation and the equilibrium Cr(VI) distribution data explain the Freundlich isotherm model (R2 = 0.998) equation, which anticipates the multi-layered adsorption on heterogeneous sites of the adsorbent. A negative value of the Gibbs free energy change indicates that the Cr(VI) adsorption over HCCO surfaces is spontaneous. The positive enthalpy change indicates the endothermic nature of the said reaction. © 2024 Taylor & Francis Group, LLC.
l-Valine Assisted Pyrene Functionalized Gold Nanoparticles Based Interface for Electrochemical Detection of Chloramphenicol Antibiotics
(John Wiley and Sons Inc, 2025) Gargi Mishra; Ankur Srivastava; Roshani Singh; Mrituanjay D. Pandey; Jay Singh
In this study, we have prepared a novel V-Py-functionalized AuNP/ITO electrode platform with excellent selectivity and reproducibility for CAP, even in the presence of a mixture of antibiotics. Here, gold nanoparticles were functionalized by a novel pyrene conjugated valine analogue(V-Py). These V-Py/AuNPs were successfully characterized by standard structural and morphological techniques such as powder XRD, Fourier transform infrared spectroscopy (FT-IR), UV–visible, and fluorescence spectroscopy, and transmission electron microscopy (TEM) techniques. The prepared V-Py/AuNPs were electrophoretically deposited on an indium tin oxide (ITO) glass plate using the electrophoretic deposition (EPD) technique. The electrochemical properties of prepared V-py/AuNPs/ITO were examined by the cyclic voltammetry (C/I/TOV) technique. Electrochemical response studies using the V-Py/AuNPs/ITO electrode for CAP estimation shared a linear progression in the concentration range of 1–150 µM. The limit of detection (LOD) and sensitivity of the electrode were found to be 3.79 × 10−2 µM and 5.08 × 10−3 mA/µM × cm2, respectively, with a response time of 15 s. This study presents a novel V-Py-functionalized AuNP platform with tremendous reusability and selectivity toward CAP, even in the presence of a mixture of antibiotics, which are the key highlights of this work. © 2025 Wiley-VCH GmbH.
Modelling soil temperature at multiple depths in Saurashtra region (Junagadh) of Gujarat using machine learning and shapely approach
(Springer Nature, 2025) Utkarsh Kumar; Rashmi; Ankur Srivastava; H. V. Parmar; H. H. Mashru; Parthsarthi A. Pandya; G. V. Prajapati; H. D. Rank
Forecasting soil temperature (ST) at multiple depths is crucial for understanding meteorological processes, enhancing agricultural resilience, and assessing ecological and environmental risks. Data driven model represents an alternative tool to the conventional measurement of ST e.g. soil thermometer. To develop the ML model, weekly ST and relevant meteorological variables for the city of Junagadh (Saurashtra region) are collected for the period of 2010–2023. A thorough feature analysis was performed to select the most promising feature using Pearson correlation coefficient and shapely approach. The model was developed using different combinations of input parameters (M1–M7) and trained using different machine learning algorithms. This research aims to evaluate four different machine learning approaches namely, Random Forest (RF), Gradient Boosting Regression (GBR), Support Vector Regression (SVR), and Long Short-Term Memory (LSTM), to predict the soil temperature at 5 cm, 10 cm and 20 cm depth. The result of this study showed that by choosing the optimum input parameter, there is no significant impact on accuracy of model. The best performance was obtained for Model 7 f(TDB, TMax, TMin, Evapo) model at the 10-cm soil depth, as it provided the greatest correlation coefficient (r = 0.9967) and the lowest value for root mean square error (RMSE = 0.3410 °C) and percent bias (PBIAS = − 0.0115). The result showed that model performance differences are often statistically significant, especially at shallower depths (ST5, ST10), but less so at ST20. In the current study, besides evaluating the potential of four machine learning models, the interpretation of the machine learning algorithm for soil temperature prediction was explored using SHapley Additive exPlanations (SHAP). The study used an explainable artificial intelligence (XAI) approach to provide novel interpretation and insights to elucidate model formulation and relative predictor importance. © The Author(s) 2025.
Nanomaterial based on microorganisms for energy storage applications
(Elsevier, 2025) Ankur Srivastava; Amit Kumar Pathak; Chhama Awasthi; Jay Singh; Mrituanjay D. Pandey
Microorganisms based on nanomaterials have attracted considerable attention due to their vigorous properties of remarkable chemical stability, water-holding capacity, specific surface area, and good mechanical strength. The advantage of microorganism-based nanomaterials is that they provide environment-friendly synthetic procedures. These intriguing features make microorganisms suitable for fabricating versatile two and three-dimensional nanomaterials to develop flexible scaffold materials. This book chapter presents a systematic, comprehensive, and modern view of developing microorganism-based nanomaterials for energy storage. The book chapter contains a brief introduction to the source of microorganisms, microstructure, and nature of microorganisms, as well as the suitable reasons behind the appropriate candidate for the synthesis of nanomaterials like metal oxide and metal hydroxide nanocomposites, doped nanomaterials, porous nanomaterials, and carbon-based nanomaterials for energy storage applications. Moreover, we provided significant research for energy storage applications like lithium-ion batteries, sodium-ion batteries, and supercapacitors, and lithium-sulfur batteries. Finally, we have also given prospects, challenges, and opportunities in designing functional nanomaterials from microorganisms for energy systems. © 2026 Elsevier Inc. All rights reserved.
Nanostructured WS2@Chitosan-Modified Screen-Printed Carbon Electrodes for Efficient Amperometric Detection of Histamine
(American Chemical Society, 2025) Diksha Singh; Ankur Srivastava; Vivek K. Chaturvedi; Jay Singh
Histamine, a pivotal chemical within certain cells of the human body, is responsible for eliciting various allergic symptoms, such as sneezing and a runny nose. In cases of allergies, where the immune system misidentifies typically harmless substances, such as certain foods or dust, as harmful, an efficient histamine sensor becomes imperative. This research introduces a novel sensing platform by employing a material comprising hydrothermally synthesized WS2 nanosheets and using this with a chitosan (CS) biopolymer on a screen-printed carbon electrode (SPE). Integrating WS2 and CS components on the SPE via drop-casting synergistically enhances conductivity and various sensor properties. This novel hybrid material combines organic CS and inorganic WS2 components applied for nonenzymatic histamine detection via differential pulse voltammetry. This study also included crystallite size determination and surface morphology assessment through characterization of the synthesized WS2 nanosheets. On the surface of the SPE, WS2 and CS were drop-casted. It is recommended that histamine be electrochemically measured on modified WS2/CS/SPE electrodes. Histamine measurements were conducted within a linear coverage of 1-100 μM, with a limit of detection of 0.0844 μM and sensitivity of 1.44 × 10-4 mA/μM cm2. The developed sensor exhibited notable levels of sensitivity, selectivity, stability, and repeatability, along with an extended linear range. The sensing technique was consequently employed to detect the histamine levels in packed food items like fermented food samples (cheese, tomato sauce, tomato ketchup, and soy sauce) at room temperature (25 °C). The findings recommend the utilization of electrochemical sensing on modified WS2/CS/SPE electrodes for accurate histamine detection. © 2025 The Authors. Published by American Chemical Society.
Ni(II)/Yb(III)-metallogels for distinctive fluorescent ‘turn-on’ detection of m-phenylenediamine: Toward construction of multiple logic gates
(Elsevier B.V., 2025) Vaishali Singh; Ankur Srivastava; Mrituanjay D. Pandey; Rampal Pandey
New versatile Schiff base gelator (HL) and its highly selective Ni(II)-and Yb(III)-based metallogels 1–2 have been synthesized and characterized by spectral techniques. Gelator HL in presence of triethylamine (Et3N) with Ni(NO3)2·6H2O and anhydrous Yb(NO3)3 in DMF/MeOH(1:1) solvents forms MG1 and MG2 supramolecular gels, respectively at room temperature (rt). Rheological results show thermal stability up to 100 ℃ and structurally rigid nature of MG1 and MG2. Remarkably, MG1 and MG2 were examined for identification of cations, anions, nitroaromatics and aromatic amines (AAs) but unable to recognize any analytes except for m-phenylenediamine (MPD) by using MG1. Metallogel MG1 shows highly selective response to MPD environmental pollutant with a limit of detection (LoD) of 7.58 × 10-7 M, without any interference of competing analytes. Interestingly, depending upon fascinating fluorescent On-Off-On switching behavior, molecular logic device has been fabricated with AND and IMPLICATION-logic gates function by employing the chemical inputs (i) HB, Ni(II) (MG1), Yb(III) (MG2) and (ii) HB, MG1 and MPD based on emission change at different wavelengths as output signal. © 2024 Elsevier B.V.
Photocatalysis by Metal–Organic Frameworks (MOFs): An Overview
(Springer Nature, 2022) Ankur Srivastava; Manju Yadav; Bani Mahanti; Arun Kumar; Mrituanjay D. Pandey
Metal–organic frameworks (MOFs) are porous crystalline materials with sequential unique characteristics, such as wide surface vicinity, high content of transition metals, porosity, and tunable physical properties after synthesis, and this makes itself in the group of heterogeneous catalysts. The MOFs composites tagged with featured metals and nanoparticles consist of eminent prospects in many applications such as photocatalytic reduction of harmful oxides of nitrogen and carbon, H2 generation, and environmental debris treatment. Furthermore, various strategies have been designed to amend the MOFs for photocatalytic performance enhancements, such as the mixed-metal/linker approach, metal ion/ligand immobilization approach, loading metal nanoparticles, and magnetic recycling. In addition, light-mediated catalysis, viz photothermal catalysis, and photocatalysis, show vital efforts in the conversion of solar energy to chemical/thermal energy through the interaction of light with matter. This catalytic effort and the interrelated recent researches against the challenge of insufficient solar light utilization have been presented here briefly in a few headings. The work toward obtaining a stable technology, low-cost applications, and future development on account are also presented. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022.
Preparation and Characterization of Nanohybrid La2O3-K Complexes for Electrochemical Study
(Institute of Physics, 2022) Ankur Srivastava; Jay Singh; Rampal Pandey; Mrituanjay D. Pandey
In biomedical science, alkali metal potassium plays a conspicuous role in the neurotransmission known as sodium (Na)-potassium (K) pump. The rare earth metal like lanthanum is most applicable in the magnetic resonance imaging technique (MRI) for cancerous cell detection. Keeping in mind this perspective, we synthesized the hybrid of La2O3 nanomaterial and K-complexes [(µ2-4-N,Ndimethylamino benzoate-κO)(µ2-4-N,N-dimethylamino benzoic acid-κO) (4-N,N-dimethylamino benzoic acid-κO) potassium(I) coordination polymer)] (nanohybrid La2O3- K complex) by hydrothermal method, whereas the potassium complex has been synthesized by the 6 hours reflection of the 4-(diethylamino) benzoic acid and potassium hydroxide in the methanol as solvent. The1H, 13C NMR, HRMS, and single-crystal investigation have been carried out for the potassium complex. Moreover,the structural, morphological, and electrochemical estimation of synthesized nanocomposites are also under process, which involves the investigation by X-ray diffraction (XRD), Fourier transform infrared (FTIR), UV- visible spectroscopy. © The Electrochemical Society
Pyrene-Appended Luminescent Probes for Selective Detection of Toxic Heavy Metals and Live Cell Applications
(John Wiley and Sons Inc, 2024) Ankur Srivastava; Gargi Mishra; Amit Kumar Pathak; Saurabh Pandey; Chhama Awasthi; Mrituanjay D. Pandey; Kamalakanta Behera
Heavy metal contamination has become a global environmental problem and currently drawn much attention from researchers in worldwide. High exposure to heavy metals can lead to problems like kidney, liver and brain damage, skin and lung cancer, etc. Rapid and sensitive detection of heavy metals is of immense importance in environmental monitoring. Over the past few decades, enormous efforts have been made to design various sensors to identify and monitor these harmful metal ions. In Comparison with other methods, fluorescence-based chemosensors have received extensive attention because of the advantages of high sensitivity, low cost, real-time monitoring, simple operation, etc. The pyrene derivatives are significant polycyclic aromatic hydrocarbons (PAHs) with strong fluorescence. They are widely used as fluorescent probes in many applications due to their easy modification, high fluorescence quantum yield, and strong fluorescence emission in live cells, outstanding cell permeability, and very low cytotoxicity. The SDG 6: Clean water and sanitation alarm a strong strategy, and careful identification of the risk connected to environmental pollutants needs urgent attention in this situation. Therefore, we highlight different types of pyrene-based fluorophores and the fluorescence mechanisms for the sensitive and selective detection methodology of Arsenic, Mercury, Cadmium, Lead, and Chromium heavy metals. © 2024 Wiley-VCH GmbH.
Quantum-sized Ag nanoparticle conjugates on biofunctionalized La2O3-rGO ternary nanocomposite-based platform for the electrocatalytic determination of dopamine
(Royal Society of Chemistry, 2023) Ankur Srivastava; Kshitij RB Singh; Mrituanjay D. Pandey; Jay Singh
In order to synthesize distinctive ternary nanocomposites, this study combines nanostructured lanthanum oxide (La2O3), reduced graphene oxide (rGO), and quantum size (5-6 nm) silver nanoparticles (AgNPs). La2O3 does not aggregate when AgNPs are introduced with rGO, which also increases bioactivity for the immobilization of biomolecules. Further, effective surface contacts are made possible by the functional groups of rGO and hexagonal La2O3 nanoparticles and the large surface area of rGO increases the electrical conductivity of its electron clouds. The rGO and La2O3 (L) are conjugated with AgNPs using an ex situ hydrothermal technique to create L-rGO/Ag nanocomposites. Prepared ternary L-rGO/Ag nanocomposites have been confirmed using various characterization methods, such as XRD, FT-IR, UV-visible, PL, Raman, SEM, TEM, and EDAX. Further, the tyrosinase enzyme has been immobilized onto the L-rGO/Ag/ITO electrode for electrochemical dopamine biosensing via DPV analysis. Standard dopamine samples were investigated in the range of 1 to 95 μM and the bioelectrode displayed outstanding sensitivity of 24.32 × 10−4 mA μM−1 cm−2 for lower concentrations (1-35 μM) and 20.88 × 10−4 mA μM−1 cm−2 for higher concentrations (40-95 μM), and limit of detection (LOD) of 0.34 μM. In addition to this, the bioelectrode exhibits 40 days of stability, minimal interference, and 8 cycles of reusability without significant deterioration. Its low Michaelis-Menten constant (Km) value of 3.70 μM emphasizes its great dopamine sensitivity and affinity. Hence, the use of this bioelectrode in real sample analysis is motivated by the encouraging results in standard sample analysis of dopamine, opening possibilities for a variety of useful practical applications for timely monitoring and managing neurodegenerative disordered. © 2023 The Royal Society of Chemistry