Browsing by Author "Avanish Singh Parmar"

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Biobased Polyimine Vitrimers: Promising Materials for Fluorescence Quenching, Anticounterfeiting, and Plastic Degradation
(American Chemical Society, 2025) Akanksha Rai; Manisha Pandey; Shikha Tripathi; Avanish Singh Parmar; Kalluri Venkata Sri Ranganath
Using glucose, one of the readily available biomasses provides an industrially relevant derivative 5-hydroxymethyl furfural (5-HMF) containing two versatile functionalities. 2,5-Furandicarbaldehyde (DFF) has been synthesized in high yields via chemo-selective oxidation of 5-HMF. Biobased thermoset vitrimers were prepared by the condensation of DFF with various amines such as polyethylenimine, Bis[4-(4-aminophenoxy)-phenyl] propane (BAPP), 1,4-diaminobutane, and (l)-Lysine. This paper reports the design, synthesis, and characterization of fluorescent biobased vitrimers and poly imines for sensing of various aromatic monoamines, diamines, and also Pd metal. It was further demonstrated that biobased polyimine vitrimers are apt as anticounterfeiting material, for plastic degradation, and for synthesis of nanoparticles in an effective way. The fluorescent material offered good thermal stability and obeyed the property of pseudoplasticity having Non-Newtonian fluids. © 2025 The Authors. Published by American Chemical Society.
Biogenic synthesis of gold nanoparticles using dual extract of tulsi–Vinca for breast cancer tumor regression in mice
(Newlands Press Ltd, 2023) Ravi Pratap; Karishma Niveria; Saurabh Kumar Srivastava; Shilpi Chaudhary; Poonam Sharma; Anita K. Verma; Avanish Singh Parmar
Aim: This work aims to synthesize the gold nanoparticles (GNPs) using a dual extract of tulsi and Vinca (T+V-Gold) for breast cancer tumor regression. Methods: The GNPs were synthesized and characterized for their microscopic, spectroscopic and crystalline properties. Further, the GNPs were investigated for in vitro and in vivo studies for the treatment of the 4T1-induced triple-negative breast cancer murine model. Results: The GNPs for 4T1 tumor-challenged mice resulted in delayed tumor development and lower tumor burden, with T+V-Gold demonstrating the highest prevention of tumor spread. The antitumor effect of T+V-Gold is highly significant in the glutathione family antioxidants glutathione S-transferase and glutathione in tumor tissue samples. Conclusion: The bioefficacy and anticancer outcomes of T+V-Gold nanoformulation can be used as therapeutic agents and drug-delivery vehicles. © 2023 Newlands Press Ltd. All rights reserved.
Deciphering interaction between chlorophyll functionalized carbon quantum dots with arsenic and mercury toxic metals in water as highly sensitive dual-probe sensor
(Elsevier B.V., 2022) Md Bayazeed Alam; Nurul Hassan; Kedar Sahoo; Manoj Kumar; Manju Sharma; Jayeeta Lahiri; Avanish Singh Parmar
Rapid and reliable heavy metal detection in drinking water is critical in developing countries as they cause serious health hazards. In this work, a novel chlorophyll functionalized CQD (ChlCQD), is presented as a nanoprobe for the sensitive detection of As3+ and Hg+ ion in aqueous solutions. These CQDs are fabricated using a one-step hydrothermal treatment of Banana leaf extract. We demonstrate that by tuning the temperature of hydrothermal synthesis from 120 °C to 230 °C we can get CQDs with different optical properties. The CQDs synthesized at 120 °C and 160 °C only are decorated with chlorophyll functional groups, while the CQDs synthesized at 200 °C and 230 °C do not have any chlorophyll groups. These chlorophyll groups give rise to a fluorescence band near the red region which gets either quenched or enhanced with the addition of metal ions. We demonstrate that the ChlCQDs synthesized at 160 °C can be utilized as a turn-off and turn-on sensor for selective detection of Hg+ ions and As3+ ions, with low limits of detection. Using surface-sensitive X-ray photoelectron spectroscopy measurements, we demonstrate that As3+ binds strongly with the carbonyl group of the chlorophyll moiety while the Hg+ ions bind very weakly to the carbon atoms of the CQDs. The theoretical calculations using Density Functional Theory (DFT) were performed to gain atomic-level insight into the interactions of As3+ and Hg+ with the surface of ChlCQD (low-temperature model surface). A strong absorption peak around 660 nm occurs due to strong overlap between As3+ and CQD surface and this peak is absent for Hg+ due to negligible overlap between orbitals of Hg+ and ChlCQD surface. As3+ and Hg+ show similar interaction with different sites on CQD (high-temperature model structure) and is consistent with observed similar experimental absorption spectra for both the metals. © 2022 Elsevier B.V.
Effect of carbon quantum dots derived from extracts of UV-B-exposed Eclipta alba on alcohol-induced liver cirrhosis in Golden Hamster
(Springer Nature, 2023) Kshama Rai; Kanchan Yadav; Megha Das; Shilpi Chaudhary; Kaustubh Naik; Priya Singh; Ashutosh Kumar Dubey; Sanjeev Kumar Yadav; Shashi Bhushan Agrawal; Avanish Singh Parmar
The Eclipta alba plant is considered hepatoprotective, owing to its phytoconstituents wedelolactone. In the current study, effect of elevated ultraviolet-B (eUV-B) radiation was investigated on biochemical, phytochemical, and antioxidative enzymatic activities of E. alba (Bhringraj) plant. The UV-B exposure resulted in an increase in oxidative stress, which has caused an imbalance in phytochemical, biochemical constituents, and induced antioxidative enzymatic activities. It was observed that the UV-B exposure promoted wedelolactone yield by 23.64%. Further, the leaf extract of UV-B-exposed plants was used for the synthesis of carbon quantum dots (CQDs) using low cost, one-step hydrothermal technique and its biocompatibility was studied using in vitro MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay on HepG2 liver cell line. It revealed no toxicity in any treatment groups in comparison to the control. Both CQDs and leaf extract were orally administered to the golden hamster suffering from alcohol-induced liver cirrhosis. In the morphometric study, it was clearly observed that a combination of UV-B-exposed leaf extract and synthesized CQDs delivered the best result with maximum recovery of liver tissues. The present study reveals the positive impact of UV-B exposure on the medicinally important plant, increased yield of wedelolactone, and its enhanced hepatoprotective efficacy for the treatment of damaged liver tissues. Graphical Abstract: [Figure not available: see fulltext.]. © 2023, The Author(s), under exclusive licence to European Photochemistry Association, European Society for Photobiology.
Effect of carbonaceous oil palm leaf quantum dot dispersion in nematic liquid crystal on zeta potential, optical texture and dielectric properties
(Springer Medizin, 2021) Ayushi Rastogi; Fanindra Pati Pandey; Avanish Singh Parmar; Shri Singh; Gurumurthy Hegde; Rajiv Manohar
In the present work, the dispersion of oil palm leaf based carbonaceous quantum dots (OPL QDs) in nematic liquid crystal (NLC) E 48 eutectic mixture has been reported. The dispersed systems with concentrations 0.1, 0.2, and 0.3 wt% are designated respectively, as MIX 1, MIX 2, and MIX 3. The objective of this study is to analyze the results on the zeta potential, optical texture, dielectric constant, dielectric loss, conductivity, dielectric strength, relaxation frequency, specific power loss and total power loss of pure and OPL QDs dispersed nematic E 48 system. Zeta potential measurement has been performed in the solution state to ensure dispersion stability. The optical textures and dielectric results are recorded after filling the respective samples in sample cells. The core findings in the present study show that the zeta potential varies from − 23.43 mV to + 28.07 mV that signifies the stability of OPL QDs suspension in LCs. Specific power loss (SPL) and total power loss (TPL) are found to be least for MIX 1 which shows that the problem of high power consumption in LCDs can be resolved by dispersing a small weight percent concentration of OPL QDs in LC medium (MIX 1). Improved molecular alignment in the dispersed system has been observed from the textural study which finds its application in good contrast display devices. The color change in the aligned textures with temperature has been attributed to the birefringence change. The porous nature of carbonaceous OPL QDs has its application in supercapacitors. The benchmark results of this study highlight the effect of temperature and frequency on dielectric parameters for both planar and homeotropic state of E 48 LCs. OPL QDs dispersed system display increased conductivity for MIX 3. The decrease in the activation energy for OPL QDs dispersed system in comparison to pure LC material E 48 is a consequential result of the potential barrier change. The increment in the dielectric strength and relaxation frequency of OPL QDs dispersed system is noticed in comparison to pure E 48. These outcomes open the door for the applicability of present LCs in the field of both display and non-display devices like sensors, supercapacitors, low power consumption displays, energy conversion, and electrical storage devices as well as advanced smart systems. Graphical abstract: [Figure not available: see fulltext.]. © 2021, Islamic Azad University.
Enhancing physical characteristics of thermotropic nematic liquid crystals by dispersing in various nanoparticles and their potential applications
(Institute for Ionics, 2023) Ayushi Rastogi; Archana Mishra; Fanindra Pati Pandey; Rajiv Manohar; Avanish Singh Parmar
Herein, we have summarized the doping of thermotropic nematic liquid crystals (LCs) with different nanoparticles (NPs) and its consequences on dielectric, optical, and electro-optical properties. The challenging task is to improve the physical properties of nematic LCs for its applications in nanotechnology, which include sophisticated and highly advanced modern displays, tunable lenses, sensors, etc. The negative effects that affect the overall performance of LCs devices are image sticking problem, image flickering, and slow response time which is mainly affected by ions and alignments. The trapping of charged ionic impurities and suppression of screening effect through NPs in LC medium produces strong electric field and van der Waal forces linked with the LC molecules and the alignment layers. The electric field controls the orientation of LC molecules and thus transforms its physical behavior. In this article, we have summarized and discussed the physical properties of thermotropic nematic LCs with the dispersion of NPs. These thermotropic LCs require improvement in their properties for the better functioning of LC products. A decade of enthusiastic research has designed the lane to the suspension of NPs in LC matrix for resolving the issues on nanotechnology. NPs (guest) that are embedded in LCs (hosts) influence its material parameters. The present article focuses on the review of published articles which report various types of NPs (metal oxide NPs, carbon-based NPs, semiconducting NPs, ferroelectric (FE) such as BaTiO3, magnetic NPs, and metallic NPs) as dopants and its sound realization on the physical properties of thermotropic nematic LCs. The topological defects and the effect of dispersion of colloidal particles in nematic LCs have been discussed. The decrease in the anchoring energy with decreasing radius of particles has been revealed. This review considers the significant role of NP self-assembly in LC medium which depends on its shape, size, and surface chemistry that affect the orientation order of LC molecules. From the application point of view, this review provides the literature support where the mixing of LCs and NPs solves the technological problems. The explanation on the improvement in the performance/material parameters is well supported by the experimental literature study reported in this review. © 2022, Qatar University and Springer Nature Switzerland AG.
Ferroelectric liquid crystal nanocomposites: recent development and future perspective
(Taylor and Francis Ltd., 2018) Satya Prakash Yadav; Kanchan Yadav; Jayeeta Lahiri; Avanish Singh Parmar
In recent years, dispersion of nanomaterials in liquid crystal media has attracted a great deal of attention for their applications in various fields and basic understanding. In this regard, nanocomposites of ferroelectric liquid crystals hold a great promise for technological advancement in displays, sensors, development of hybrid materials for optical applications and others. With the emphasis on the properties of ferroelectric liquid crystals, this paper presents a summarizing overview with critical comments on the progress made in last one decade in understanding the influence of nanoparticles on the ferroelectric liquid crystals. The dispersion of nanoparticles in liquid crystal (host material) significantly influences its properties, thereby making the dispersed material more promising for potential applications. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.
Hexagonal Boron Nitride as Anode for Sodium-Ion Battery - A Reality Check!
(Institute of Physics, 2023) Shubham Garg; Avanish Singh Parmar; None Rosy
Sodium-ion batteries (SIBs) have gained enormous attention as an alternative electrochemical energy storage system. A significant challenge for its practical viability is finding an anode material that can provide high specific capacity along with good cycling stability. Recently, numerous theoretical works have proposed hexagonal boron nitride (hBN) as a promising anode material for SIBs. Nevertheless, there has been no reported experimental verification for the said theoretical claims. To fill the knowledge gap, here, the electrochemical performance of hBN has been investigated under the capacity of a potential anode for SIBs. The effect of particle morphology on the electrochemical performance of hBN has also been investigated using bulk hBN powder and nanoplatelets hBN as active materials. Unexpectedly, hBN showcased minimal charging capacity with effectively no reversible intercalation/de-intercalation of Na-ions. The obtained results provide experimental insight into the ineffectiveness of hBN in serving as SIB anode material, unlike the previous theoretical claims. We believe it is essential to report these discrepancies in the computational and experimental findings for the benefit of experimentalists working enthusiastically to explore and develop new anode materials related to boron nitride systems. © 2023 The Electrochemical Society (“ECS”). Published on behalf of ECS by IOP Publishing Limited.
Hexagonal Boron Nitride Decorated Polypropylene Separator for Dendritic Free Sodium Deposition and Stripping
(Institute of Physics, 2023) Shubham Garg; Ankush Kumar Singh; Avanish Singh Parmar; Rosy
Sodium metal, with its impressive electrochemical properties, including a high specific capacity of 1166 mAhg−1 and a low redox potential of −2.71 V vs SHE, emerges as a compelling option for battery anodes. However, the dendrites formed during subsequent charging/discharging cycles severely limit its practical implementation. Here, we report the ability of hexagonal boron nitride (hBN) coated polypropylene separator to suppress the dendritic deposition. The tailored separator manifests improved wettability and stable electrochemical performance under limited Na availability. The improved performance is ascribed to the sodiophilic character of hBN, which is expected to provide uniform Na+ flux and exhibit a guiding effect for uniform Na deposition. This study aims to report the use of a hBN coated separator for mitigating Na dendrites; however, comprehensive research is required to properly evaluate the pragmatic application of the proposed strategy in metal batteries. © 2023 The Electrochemical Society (“ECS”). Published on behalf of ECS by IOP Publishing Limited.
Influence of growth parameters on the dopant configuration of nitrogen-doped graphene synthesized from phthalocyanine molecules
(Springer, 2022) Naresh Shyaga; Rahul Sharma; Nurul Hassan; Md Bayazeed Alam; Avanish Singh Parmar; Jayeeta Lahiri
Synthesis of nitrogen-doped graphene (NDG) via chemical vapor deposition (CVD) using phthalocyanine, a solid precursor containing carbon and nitrogen, is reported. The effect of the growth parameters (temperature, time, and carrier gas) on the surface morphology, dopant configuration, and conductivity of the films was studied. The NDG films were synthesized at different substrate temperatures of 1050 °C, 950 °C, and 850 °C for different growth times of 5–15 min in the presence of an Ar + H2 gas mixture. Significantly, pyrrolic-N type defects are observed predominantly after 5 min of growth time. At 1050 °C, pyrrolic N content is around 45.4% after 5 min of growth which decreased to 24.1% after 15 min of growth, while the graphitic-N content increased from 41.2 to 76% at the same time. It is demonstrated that the conversion of pyrrolic type of nitrogen to graphitic nitrogen defects can be arrested by changing the carrier gas from Ar + H2 to Ar. The pyrrolic-N content increased to 64% by changing the gas from Ar + H2 to Ar at 15 min. The electrolyte gated field-effect transistors were fabricated using the obtained films, and dopant-dependent mobility was observed. The mobility for pyrrolic-N-dominated film is 13.6 cm2 V−1 s−1 increasing to 62.8 cm2 V−1 s−1 for graphitic-N-dominated film. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Investigation of dielectric and optical properties of pure and diamond nanoparticles dispersed nematic liquid-crystal PCH5
(Taylor and Francis Ltd., 2021) Dhananjay Kumar Gaur; Ayushi Rastogi; Harshita Trivedi; Avanish Singh Parmar; Rajiv Manohar; Shri Singh
In the present work, we have dispersed diamond nanoparticles (DNPs) in nematic liquid crystal 4-(Trans-4ʹ-n-Pentylcyclohexyl) Benzonitrile (PCH5) and studied the dielectric and optical properties of pure and DNPs dispersed nematic systems. We have investigated the effect of dispersion of DNPs (concentrations 0.5 and 1.0 wt%) in nematic liquid crystals (NLC) PCH5 on the dielectric permittivity, dielectric loss, dielectric anisotropy, photoluminescence, UV-Vis absorbance. It has been found that these properties are influenced by the dispersion of DNPs in nematic PCH5 system and applied electric field. Due to the dispersion of DNPs (1.0 wt% concentration) in PCH5, a significant decrease in the relative permittivity occurs. The relaxation peaks of dielectric loss shifts towards higher frequency side for NLC-DNPs composites. The dielectric anisotropy has been found to decrease with the dispersion of DNPs into pure NLC. The PL emission and UV-Vis absorbance for the dispersed systems have been decreased. An effort has been made to explain the observed results on the basis of interaction between nematic molecules and diamond NPs. The possible applications have also been suggested for the dispersed systems in this study. © 2020 Informa UK Limited, trading as Taylor & Francis Group.
Investigation of dielectric, optical and zeta potential properties of pure and zinc ferrite nanoparticles dispersed nematic liquid crystal PCH5
(Springer Science and Business Media Deutschland GmbH, 2022) Dhananjay Kumar Gaur; Fanindra Pati Pandey; Ayushi Rastogi; Avanish Singh Parmar; Rajiv Manohar; Shri Singh
The present work reports the results on dielectric and optical properties, and zeta potential of pure and zinc ferrite magnetic nanoparticles (ZnFe2O4 NPs) dispersed nematic liquid crystals (NLC) 4-(trans-4'-n-pentylcyclohexyl) benzonitrile (PCH5). The ZnFe2O4 NPs of three different concentration 0.25, 0.5 and 1.0 wt% have been dispersed in host nematic. The effect of ZnFe2O4 NP dispersion in NLC PCH5 on dielectric permittivity, dielectric anisotropy, ac conductivity, photoluminescence, Raman spectra and zeta potential has been studied. It has been observed that these properties are influenced by the concentrations of NPs in host nematic and applied electric field. Significant decrease in dielectric permittivity and dielectric anisotropy due to the presence of NPs in host nematic matrix has been observed. For the NP concentrations of 0.25 and 0.5 wt% in PCH5, photoluminescence intensity is increased, but it is decreased for the 1.0 wt% concentration of NPs in host nematic matrix. The numerical values of zeta potential are decreased with the concentrations of NPs. This result provides useful information on the stability and aggregation dynamics of the dispersed systems. In the profile of Raman spectra, variation in intensities is found for different orientations. An effort has been made to explain the observed results on the basis of interaction between NPs and nematic molecules. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.
Large area few‐layer hexagonal boron nitride as a raman enhancement material
(MDPI AG, 2021) Nilanjan Basu; Moram Sree Satya Bharathi; Manju Sharma; Kanchan Yadav; Avanish Singh Parmar; Venugopal Rao Soma; Jayeeta Lahiri
Increasingly, two‐dimensional (2D) materials are being investigated for their potential use as surface‐enhanced Raman spectroscopy (SERS) active substrates. Hexagonal Boron Nitride (hBN), a layered 2D material analogous to graphene, is mostly used as a passivation layer/dielectric substrate for nanoelectronics application. We have investigated the SERS activity of few‐layer hBN film synthesized on copper foil using atmospheric pressure chemical vapor deposition. We have drop casted the probe molecules onto the hBN substrate and measured the enhancement effect due to the substrate using a 532 nm excitation laser. We observed an enhancement of ≈103 for malachite green and ≈104 for methylene blue and rhodamine 6G dyes, respectively. The observed enhancement factors are consistent with the theoretically calculated interaction energies of MB > R6G > MG with a single layer of hBN. We also observed that the enhancement is independent of the film thickness and surface morphology. We demonstrate that the hBN films are highly stable, and even for older hBN films prepared 7 months earlier, we were able to achieve similar enhancements when compared to freshly prepared films. Our detailed results and analyses demonstrate the versatility and durability of hBN films for SERS applications. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
NiO Nanomaterial Functionalized with Organic Gel Molecules for Heterogeneous Asymmetric Catalysis
(American Chemical Society, 2024) Pranshu K. Gupta; Neeraj Kumar; Kaustubh Naik; Avanish Singh Parmar; Kalluri V.S. Ranganath
Chiral inorganic nanomaterials have a wide range of applications including sensing, catalysis, and electronics. Low molecular weight chiral organogels are widely used in organic fluids, pharmaceuticals, drug delivery, self-assembled materials, electrolytes, and liquid crystals. In this study, we report the synthesis of chiral organogels that mimic the properties of Bingham pseudoplastic with Herschel-Bulkley consistency. Furthermore, chiral NiO nanoparticles were prepared in the presence of chiral gels. The development of chiral enantiomerically pure solids for heterogeneous asymmetric catalysis is of great importance in the pharmaceutical industry. The synthesized chiral material can effectively catalyze the asymmetric Michael addition of malonates with chalcones in high yields and with excellent enantioselectivity. The potential of our catalyst was verified by recycling the catalyst in the asymmetric reaction for a number of times. © 2024 American Chemical Society.
Optical properties and zeta potential of polyvinyl pyrrolidone capped gold nanoparticles dispersed nematic liquid crystal mixture E7
(Elsevier B.V., 2023) Dhananjay Kumar Gaur; Kaushlendra Agrahari; Bhupendra Pratap Singh; Md Bayazeed Alam; Avanish Singh Parmar; Rajiv Manohar; Shri Singh
The effect of dispersion of polyvinyl pyrrolidone (PVP) capped gold nanoparticles in nematic mixture E7 on the optical properties (absorbance and photoluminescence, fluorescence life time and Raman imaging) and zeta potential is studied. The gold nanoparticles of 0.25, 0.5 and 1.0 wt% concentrations are dispersed into E7. It has been found that the absorbance and photoluminescence intensity of dispersed systems are increased and depend on the GNPs concentration. These increase correspond to the coupling between the radiation field (electromagnetic waves of the light source) and the GNPs low-energy phonons and constructive coupling of emissions between the E7 and GNPs, respectively. The change in the fluorescence lifetime of pristine and GNPs dispersed E7 systems has confirmed the energy transfer between E7 and GNPs molecules. The study of Raman spectrum shows the variations in the intensity of the Raman peaks with different orientations. Due to dispersion of GNPs in E7 the values of zeta potential are increased. This ensures the good stability of the dispersed systems. The conductivity of dispersed system has increased drastically. In conclusion, the dispersion of GNPs in host nematic mixture E7 has influenced significantly its properties, thereby making the dispersed material more promising for the potential applications. © 2023
Phase transitions in ferroelectric liquid crystals
(2008) Shri Singh; Avanish Singh Parmar; Abhilasha Singh
Molecular chirality plays an important role in the science of liquid crystals, leading to cholesteric liquid crystal, blue phases, ferroelectric and antiferroelectric smectic phases and twist grain boundary phases. In all of these mesogens, chirality is an intrinsic property built into the chemical structure of mesogenic molecules. The study of ferroelectric liquid crystals has seen substantial experimental strides. In theoretical aspects, there has been relatively little basic work on this fascinating class of material. This review will try to present a comprehensive overview of the current status of the phase transitions in ferroelectric smectic liquid crystals. The article begins with a brief introduction about the symmetry and structure of ferroelectric mesophases. An attempt is made to identify a range of problems and related questions associated with the study of phase transitions. In the remaining parts of the article the important experimental and theoretical developments are summarized. Finally, some of the future directions have been identified.
Sandalwood-derived carbon quantum dots as bioimaging tools to investigate the toxicological effects of malachite green in model organisms
(Elsevier Ltd, 2020) Devyani Shukla; Megha Das; Dipanshu Kasade; Maneesha Pandey; Ashutosh Kumar Dubey; Sanjeev Kumar Yadav; Avanish Singh Parmar
Malachite green is an N-methylated diaminophenylmethane dye that has generated much concern over its suggestive carcinogenic nature. After its excessive use in aquaculture industry as an effective ectoparasitide, much debate was raised over its toxicological effects leading to scientific studies conducted on animal models. Even after several bans, malachite green is still easily available in many parts of the world and unscrupulously even used to give green vegetables a fresher look. This study aims to address this concern by systematically studying the toxicological effects of malachite green through bioimaging in plant and animal cell and tissue. Sandalwood-derived carbon quantum dots have been used as a bioimaging tool since they are non-cytotoxic and show excellent fluorescence properties. Onion tissues demonstrate the translocation of the dye inside cells having high affinity for the nuclei and cell walls. Toxicological effects on the growth of Vigna radiata (mung beans) have been studied methodically. Bioimaging of the transverse cross-section of the dye-treated plant root shows a significant difference from the control. In animal cells, dose-dependent decrease in cell viability of MG-63 cells was observed with MG. CQD showed good fluorescence in both cytoplasm and nucleus of MG63 cells. In addition, CQDs were employed as a great tool for bioimaging of the histopathologically adverse effects of MG in Golden hamster animal model. This study showed CQDs could be used as an alternative non-site specific fluorescent probe for cell and tissue imaging for better visualization of cell and tissue architectural changes. © 2020 Elsevier Ltd
Sensing of p-nitrophenol using highly selective and sensitive Boran, Nitrogen doped quantum dots
(Elsevier B.V., 2024) Ravi Pratap; Shriya Pandey; Vipul Vishal; Ishika Raghuvanshi; Sunil Kumar; Jayeeta Lahiri; Avanish Singh Parmar
p-Nitrophenol (PNP) is a nitroaromatic compound that poses a significant threat to human health and the environment due to its carcinogenic, mutagenic, cytotoxic, and embryotoxic properties at low concentrations. Therefore, the selective and sensitive detection of PNP is crucial for both human health and environmental monitoring. Boron (B) and Nitrogen (N) doped quantum dots (B,NQDs) have been found to be effective as blue-green luminescent materials for this purpose. These B,NQDs were synthesized using a one-step hydrothermal method, resulting in the formation of highly stable quantum dot. The addition of trace amounts of PNP, the luminescence of the B,NQDs was significantly quenched, which was found to be linearly dependent on the PNP concentration in the range of 100pM to 6 μM. Further analysis of steady-state absorption and emission, along with photoluminescence decay dynamics, revealed the formation of both static and dynamic quenching complexes. Our simple fluorimetry-based sensor demonstrated an impressive limit of detection (LOD) of 9.08 nM, making it highly selective and sensitive for the detection of PNP. Additionally, the B,NQDs exhibited exceptional stability with respect to pH, UV exposure, salinity, and storage conditions. Finally, we successfully demonstrated the detection of PNP in real water systems and pesticides. © 2024 The Authors
Skin Adhesive 3D-Printable BSA-Amyloid/Cellulose Hybrid Hydrogel Film for Rapid Wound Healing and Skin Regeneration with Enhanced Antioxidant and Anti-Inflammatory Properties
(American Chemical Society, 2025) Saurabh Kumar Srivastava; Shikha Tripathi; Sakshi Agarwal; Rahul Ranjan; Somesh Agrawal; Prodyut Dhar; Eugene B. Postnikov; Shilpi Chaudhary; Vinod N. Tiwari; Avanish Singh Parmar
Natural polymer-based hydrogels closely mimic the extracellular matrix, making them ideal for supporting cell growth and tissue regeneration. Recent advancements in tuning their porosity, morphology, and size have helped overcome key challenges in tissue engineering, such as vascularization and multicellular integration. However, their clinical use is often limited by drawbacks, such as low mechanical strength, structural instability, high production costs, and limited reproducibility. In this work, we present a skin-adhesive, 3D-printable/injectable hybrid hydrogel composed of natural protein and cellulose. This hybrid hydrogel overcomes the limitations of conventional systems by enhancing mechanical strength, scaffold stability, reproducibility, cost-effectiveness, and adhesive properties while preserving high biocompatibility and biodegradability. Using the same formulation, a wound dressing material is fabricated and applied at the wound site either by suturing or as an adhesive film. Furthermore, the hydrogel exhibits inherent antibacterial, antioxidant (60% of radical scavenging), anti-inflammatory, cell viability (up to 90%), and cell migration properties that significantly promote wound healing. This multifunctional hybrid hydrogel offers a promising solution for next-generation wound dressing applications and contributes to the advancement of bioactive and customizable materials in regenerative medicine. © 2025 American Chemical Society
Synthesis and characterization of novel protein nanodots as drug delivery carriers with an enhanced biological efficacy of melatonin in breast cancer cells
(Royal Society of Chemistry, 2021) Kanchan Yadav; Megha Das; Nurul Hassan; Archana Mishra; Jayeeta Lahiri; Ashutosh Kumar Dubey; Sanjeev Kumar Yadav; Avanish Singh Parmar
Melatonin is a potent antioxidant, chemotherapeutic and chemo preventive agent against breast cancer. However, its short half-life is one of the major limitations in its application as a therapeutic drug. To overcome this issue, the green-emitting protein nanodot (PND) was synthesized by a one-step hydrothermal method for loading melatonin. The synthesized pH-7 and pH-2 PND showed a quantum yield of 22.1% and 14.0%, respectively. The physicochemical characterization of both PNDs showed similar morphological and functional activities. Furthermore, the biological efficacy of melatonin-loaded PND (MPND) was evaluated in a breast cancer cell line (MDA-MB-231) for live-cell imaging and enhanced nano-drug delivery efficacy. Interestingly, the permeability of neutral pH PND in both cell cytoplasm and nucleus nullifies the limitations of real-time live-cell imaging, and ensures nuclear drug delivery efficacy. Neutral pH PND showed better cell viability and cytotoxicity as a fluorescence bioimaging probe compared to acidic PND. The bioavailability and cell cytotoxicity effect of MPND on MDA-MB-231 breast cancer cells were studied through confocal and migration assay. Results showed that MPND causes enhanced bioavailability, better cellular uptake, and inhibition of the migration of breast cancer cells as compared to the drug alone. Besides, the synthesized MPND showed no sign of fluorescence quenching even at a high concentration of melatonin, making it an ideal nanocarrier for bioimaging and drug delivery. © The Royal Society of Chemistry 2021.