Publications by authors named "Lija L Raju"

12 Publications

  • Page 1 of 1

CuO loaded ZnS nanoflower entrapped on PVA-chitosan matrix for boosted visible light photocatalysis for tetracycline degradation and anti-bacterial application.

J Environ Manage 2022 Jan 11;306:114396. Epub 2022 Jan 11.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Novel photocatalyst CuO loaded ZnS nanoflower supported on carbon frame work PVA/Chitosan was synthesized by co-precipitation and ultrasonic assisted method. The co-existence of ZnS and CuO and its crystallinity in nanohybrid was verified by XRD, SAED and HR-TEM analysis. The availability of defects in ZnS was identified by EPR. FTIR and TGA verified the presence of PVA and Chitosan. Defects mediated ZnS-CuO/PVA/chitosan heterojunction promote synergistic charge separation with type II interface. Zn-vacancy facilitates two-photon excitation that improves visible-light harvesting. The photocatalytic activity of ZnS-CuO/PVA/Chitosan was 94.7% which is higher when compared to ZnS (40%) and CuO (60%). The photocatalytic mechanism was elucidated using scavenger test and both ·O and ·OH were found to play key role in tetracycline degradation. In addition, ZnS-CuO/PVA/Chitosan demonstrated efficient anti-microbial effect against the both gram strains on comparing with individual ZnS and CuO. Thus, the multifunctional ZnS-CuO/PVA/Chitosan is promising for the photocatalytic degradation of tetracycline and as an antimicrobial agent.
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http://dx.doi.org/10.1016/j.jenvman.2021.114396DOI Listing
January 2022

Synthesis and application of CdS nanoparticles-decorated core-shell [email protected] nanohybrids for visible-light spectrophotometric assay of sulfide in aqueous sample.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Dec 22;270:120793. Epub 2021 Dec 22.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Novel [email protected] nanosphere decorated with CdS NPs ([email protected] NCs) was synthesized by one step chemical synthesis method. The fabricated NCs were characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), fourier transfer infra-red spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), zeta sizer and particle size analyzer. TEM and XRD confirmed the Ag in core and Ni in shell for the effective formation of [email protected] core shell nanosphere. EDAX and XPS spectra of NCs confirms the formation of [email protected] NCs. Zeta potential and particle size of the NCs was found to be 29.5 ± 1.5 mV and 24 ± 1 nm respectively. The complete loss in the peak intensity of [email protected] NCs (localized surface plasmon resonance (LSPR)) at ∼410 nm in presence of S ions was observed which indicates its selective detection towards S ions. The sulfide ion sensing by [email protected] NCs was due to the successive oxidation of Ag results in the formulation of Ag ions in the system, which causes the diminishing of LSPR band of NCs. The limit of detection (LOD) of S ions by [email protected] NCs was calculated to be of 2.66 nM. The combination of CdS NPs with core-shell [email protected] nanosphere guides a promising strategy for S ions detection from environmental polluted samples.
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http://dx.doi.org/10.1016/j.saa.2021.120793DOI Listing
December 2021

Chitosan capped Ag/NiS nanocomposites: A novel colorimetric probe for detection of L-cysteine at nanomolar level and its anti-microbial activity.

Int J Biol Macromol 2021 Dec 10;193(Pt B):2054-2061. Epub 2021 Nov 10.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

L-Cysteine (L-cys) plays very crucial role in biological systems. The study reports the colorimetric detection of L-cys at nanomolar level using chitosan capped Ag decorated NiS nanocomposite (chit-Ag/NiS NCs).The chemical reduction and co-precipitation methods were adopted to prepare chit-Ag/NiS NCs. The fabricated NCs was characterized by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), FT-Raman, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), high-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The chit-Ag/NiS NCs particularly detect L-cys even in other amino acids presence. The chit-Ag/NiS NCs showed the surface charge of -26 ± 39.9 mV. The detection of L-cys was indicated by disappearance of yellowish-brown color of Chit-Ag/NiS NCs to colorless. A good linear correlation was found between absorbance vs logarithmic concentration of L-cys (1 μM to 1 nM) with R value of 0.99. The chit-Ag/NiS NCs impregnated cotton swabs was prepared for real time detection of L-cys and the prepared probe was found to be highly selective and specific. The effect of pH, temperature and salinity influencing the L-cys detection was studied. Also, the antimicrobial activity of Chit-Ag/NiS NCs was investigated against gram negative (E. coli) and gram positive (B. subtilis) bacteria.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.11.037DOI Listing
December 2021

Ag decorated CrS NPs embedded on PVP matrix: A colorimetric probe for selective and rapid detection of sulphide ions from environmental samples.

Spectrochim Acta A Mol Biomol Spectrosc 2022 Jan 6;264:120253. Epub 2021 Aug 6.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Globally, the environmental pollution is one of the major issues causing toxicity towards human and aquatic life. We have developed a facile and innovative sensing approach for detection of sulphide ions (S) present in the aqueous media using Ag decorated CrS NPs embedded on PVP matrix (Ag/CrS-PVP). Based on the SPR phenomena, the detection of S ions was established. The nanohybrid was characterized using various techniques such as UV-vis spectrophotometer, High-Resolution Transmission Electron Microscopy (HR-TEM), Thermal Gravimetric Analysis (TGA), X-ray diffraction analysis(XRD), Energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The yellowish colour of Ag/CrS-PVP nanohybrid turned to brown colour in presence of S ions. The selectivity and sensitivity of the prepared probe was studied against the other interfering metal ions. In addition, the effect of different concentration of S ions in the nanohybrid solution was investigated and the Limit of detection (LOD) was found to be 6.6 nM. The good linearity was found over the range of 10 nM to 100 μM with R value of 0.981. The paper strip based probe was developed for rapid onsite monitoring of S ions. The proposed method is found to be cost-effective, rapid, and simple. We have validated the practical applicability of the prepared probe for determining the concentration of S ions in real water samples.
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http://dx.doi.org/10.1016/j.saa.2021.120253DOI Listing
January 2022

Synthesis and characterizations of hybrid PEG-FeO nanoparticles for the efficient adsorptive removal of dye and antibacterial, and antibiofilm applications.

J Environ Health Sci Eng 2021 Jun 28;19(1):389-400. Epub 2021 Jan 28.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu India.

Purpose: Dyes are highly toxic coloured compounds in nature that are largely applied in paper, food, textile and printing industries. Here, the adsorption technique was performed to remove methyl orange (MO) dye from water by polyethylene glycol (PEG) modified iron oxide nanoparticles (FeO NPs).

Methods: The method used for FeO NPs synthesis was chemical precipitation. The particles were analyzed by transmission electron microscope, magnetometer, BET analyzer, fourier-transform infrared spectroscopy, X-ray powder diffraction, zetasizer and particle size analyzer. The influence of pH (4.0 to 10.0), NaCl concentration (0.01 mM to 2 M), adsorbent dosage (1 to 10 mg), and the role of surface charge on adsorptive removal were investigated.

Results: The NPs size, zeta potential and surface area was found to be 26 ± 1.26 nm, 33.12 ± 1.01 mV and 119 m/g respectively. The adsorption of MO on FeO NPs agreed best to Freundlich model (R = 0.965) when compared with Langmuir model (R = 0.249). By comparing pseudo-first-order kinetic model (R = 0.937), kinetic adsorption study was better followed by pseudo-second-order kinetic model (R = 1). The adsorption rate decreased with increasing NaCl concentration. At pH 4, maximum adsorption was noted. The particles were also exhibited excellent antibacterial and antibiofilm activities. The ROS formation, lipid peroxidation and oxidative stress were increased with increase in NPs concentration. The NPs precoated slides exhibited more than 50% growth inhibition.

Conclusion: The investigation denotes the versatile applications of the prepared particles for removing the dye stuffs from industrial effluents and as antibacterial and antibiofilm agent.
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http://dx.doi.org/10.1007/s40201-021-00612-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8172665PMC
June 2021

Cytotoxicological evaluation of copper oxide nanoparticles on green algae, bacteria and crustacean systems.

J Environ Health Sci Eng 2020 Dec 10;18(2):1465-1472. Epub 2020 Oct 10.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu India.

Purpose: Copper oxide (CuO) nanoparticles (NPs) have been utilized in several industries including textile, consumer products, medical, automobiles etc. The discharge of industrial effluents in environment increased the probability of CuO NPs contamination in the ecosystem.

Methods: The present investigation used CuO NPs to determine the toxic effect on species, fresh water algae isolated from natural pond, bacterial species and and a crustacean species .

Results: The NPs average diameter and zeta potential was estimated to be 45 ± 3 nm and 29 ± 1.78 mV respectively. The results showed that 0.1 µg/mL CuO NPs showed the growth inhibition of 47 ± 2% on sp. after 5 days of incubation. The CuO NPs also showed toxic effect to bacterial systems such as and and crustacean system . Further, there was an increased lipid peroxidation and generation of reactive oxygen species (ROS) in algal cells observed up on NPs exposure. The exposure of NPs suppressed the antioxidant defense system. The amount of glutathione was reduced after the exposure of NPs.

Conclusion: The study suggested the role of ROS in toxicity of algal and bacterial systems. The present study pointed out the potent toxicity of CuO NPs to the organisms present in the aquatic environment.
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http://dx.doi.org/10.1007/s40201-020-00561-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7721846PMC
December 2020

Impact of bovine serum albumin - A protein corona on toxicity of ZnO NPs in environmental model systems of plant, bacteria, algae and crustaceans.

Chemosphere 2021 May 20;270:128629. Epub 2020 Oct 20.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Zinc oxide nanoparticles (ZnO NPs) are widely applied in industrial, household and medical areas that lead to its discharge and accumulation in ecosystem. Here, the toxic effect of ZnO NPs in presence and absence of bovine serum albumin (BSA) was analyzed. The difference in toxicity of bare ZnO and BSA interacted ZnO was studied with different environmental models. P. aeruginosa and S. aureus were used as model bacterial systems. Toxicity against bacteria was determined by employing plate count method. C. pyrenoidsa was used as algal system for evaluating toxicity and it was determined by chlorophyll estimation assay. Daphnia sp. was chosen as crustacean system model. A. cepa root cells were chosen as plant model. ZnO NPs increased the ROS formation, lipid peroxidation and oxidative stress and it reduced in the presence of BSA. The cytotoxicity, chromosomal aberrations and micronuclei (MN) index of A. cepa were increased after ZnO NPs treatment. Same time the toxic effect was decreased in case of BSA coated ZnO NPs. The NPs toxic potential on the organisms decreased in the order of P. aeruginosa (LC-0.092 mg/L) > S. aureus (LC-0.33 mg/L) > Daphnia sp (LC-0.35 mg/L) > C. pyrenoidosa (LC-8.17 mg/L). LC in presence of BSA was determined to be 18.45, 26.24, 17.27 and 53.97 mg/L for P. aeruginosa, S. aureus, Daphnia sp and C. pyrenoidosa respectively. Therefore, the report suggests that BSA stabilized ZnO NPs could be more amenable towards applications in biotechnology and bioengineering.
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http://dx.doi.org/10.1016/j.chemosphere.2020.128629DOI Listing
May 2021

A potent multifunctional Ag/Co-polyvinylpyrrolidone nanocomposite for enhanced detection of Cr(III) from environmental samples and its photocatalytic and antibacterial applications.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Dec 1;243:118766. Epub 2020 Aug 1.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Trivalent chromium (Cr(III)) is considered to exhibit hormesis (bi-phasic dose-response) property, where low dose be beneficial and high dose shows toxic effect. The present work describe the development of a bimetallic Ag/Co-polyvinylpyrrolidone nanocomposite (Ag/Co-PVP NPs) probe to detect and quantify Cr(III) ions from aqueous samples. The hydrodynamic size and zeta potential of the particle was determined to be 29 ± 1.3 nm and -37.19 ± 2.4 mV respectively. The interaction of Cr(III) with Ag/Co-PVP probe showed drastic change in colour of NPs from dark brown to pale yellow, with corresponding blue shift, tapering width and increased peak intensity. The probe showed high specificity towards Cr(III) among the tested metal ions. A linearity was observed between various dilutions of Cr(III) ions (10 to 50 nM) and the absorbance of Ag/Co-PVP NPs at 428 nm with R value of 0.998. The minimum detectable limit of Cr(III) was calculated to be 0.6 nM. The influence of salinity, temperature and pH on detection was studied. The probe was found to detect Cr(III) at acidic pH effectively. Competitive metal ions did not interfere the detection of Cr(III). The water sample collected from Noyyal river was taken to estimate Cr(III) by using the prepared probe to ensure practical applicability. The sample contains 9.3 nM of Cr(III) that was cross verified with AAS analysis. Hence, it is understood that the reported probe can be used to detect Cr(III) selectively with high accuracy from aqueous samples. In addition, the particles also exhibited excellent photocatalytic activity under visible light. Ag/Co-PVP nanocomposites exhibited excellent antibacterial activity against both gram +ve (B. subtilis) and gram -ve (E. coli) bacteria.
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http://dx.doi.org/10.1016/j.saa.2020.118766DOI Listing
December 2020

Highly selective and sensitive tool for the detection of Hg(II) using 3-(Trimethoxysilyl) propyl methacrylate functionalized Ag-Ce nanocomposite from real water sample.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Dec 20;242:118738. Epub 2020 Jul 20.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Mercury and its derivates cause distinct toxicity and it is detrimental to the ecosystem where the excessive concentration contributes towards the environmental pollutants. The current study reported a colorimetric method for the detection of Hg(II) ion with high specificity and selectivity using Ag-Ce nanocomposite (NC) functionalized by 3-(Trimethoxysilyl) propyl methacrylate. The synthesized Ag-Ce NC was characterized by using double beam UV-visible spectrophotometer, zeta sizer, EDS, TEM, FT-IR, XRD and particle size analyzer. The synthesized particle possessed an average particle size of 27 ± 1 nm and zeta potential of -39.32 ± 3 mV. The brownish yellow colored Ag-Ce NC changed to colorless in presence of Hg(II) where the colorimetric detection was extremely specific and superior towards Hg(II) ion on comparing the tests with other metal ions. An excellent linear correlation was observed between absorbance (395 nm) and Hg(II) concentrations (1 nM-10 μM) (R = 0.988) with LOD of 0.03 nM. A cotton swab based probe was prepared for selective, elegant and low cost colorimetric method to detect Hg(II). The parametric study was performed for optimizing the suitable condition. The colorimetric probe developed by this study for Hg(II) detection using Ag-Ce NC shows excellent practical applicability.
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http://dx.doi.org/10.1016/j.saa.2020.118738DOI Listing
December 2020

Preparation of Ag-cellulose nanocomposite for the selective detection and quantification of mercury at nanomolar level and the evaluation of its photocatalytic performance.

Int J Biol Macromol 2020 Dec 17;164:911-919. Epub 2020 Jul 17.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Mercury is a toxic heavy metal that reaches to the water bodies mainly by coal burning, mining and petrol refining. The study was focused to investigate the application of Ag-cellulose nanocomposite to detect and quantify mercury colorimetrically. The Ag-cellulose nanocomposite was characterized by X-ray diffraction, Transmission electron microscopy, Fourier transform infrared spectroscopy, UV-visible spectroscopy, particle size analyzer and zetasizer. The study identified that the presence of other metal ions did not interfere with the detection of Hg ion by the probe. The prepared Ag-cellulose nanocomposite-phenylalanine conjugate incorporated paper strip showed an excellent result in Hg detection. The Ag-cellulose nanocomposite was used to quantify the unknown concentration of mercury on real sample (environmental sample) and it was found to be highly accurate by confirming with atomic absorption spectrophotometric analysis. The Ag-cellulose nanocomposite showed effective detection at 45 °C, pH 9 and 0.1% of salinity. The Ag-cellulose nanocomposite showed efficient photocatalytic performance under visible light irradiation. The half-life period of MB by Ag-cellulose nanocomposite under visible light was determined to be 90 min. The study suggests the application of prepared probe in photocatalysis and the detection of Hg from various environmental samples.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.07.119DOI Listing
December 2020

Colorimetric detection of mercury ions from environmental water sample by using 3-(Trimethoxysilyl)propyl methacrylate functionalized Ag NPs-tryptophan nanoconjugate.

J Photochem Photobiol B 2020 Jun 30;207:111888. Epub 2020 Apr 30.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Recent trend in the nanotechnology made an interest to make nano based system to detect the environmental pollutant including heavy metals, pesticides and antibiotics. Mercury is toxic heavy metals which causes hazardous effect to human and environmental organisms. They usually reach to the environment by mining, petrol refining and coal burning, which can change to its ionic forms according to the environmental condition. The present study was concentrated on the effective detection of Hg (II) ion from environmental sample colorimetrically by developing Ag NPs - tryptophan nanoconjugate functionalized with 3-(Trimethoxysilyl)propyl methacrylate (TMPM). The characterization of prepared particles was performed by UV-visible spectrophotometer, transmission electron microscopy (HRTEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD), particle size analyzer and zeta sizer. The size of prepared NPs was 9 ± 1.10 nm and it possess the surface charge of -37.41 ± 4 mV. Upon the interaction of Ag NPs - tryptophan nanoconjugate and Hg (II) ion, the colour of the conjugate disappeared. The effect of environmental factors (Temperature, pH and saline concentration) on Hg (II) ion detection was also investigated. The probe indicated that Ag NPs - tryptophan nanoconjugate functionalized with TMPM was found to be an efficient tool for mercury detection from various environmental water samples.
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http://dx.doi.org/10.1016/j.jphotobiol.2020.111888DOI Listing
June 2020

Rapid colorimetric detection of mercury using silver nanoparticles in the presence of methionine.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Mar 30;228:117712. Epub 2019 Oct 30.

Nanobiotechnology Laboratory, Department of Biotechnology, Bannari Amman Institute of Technology, Sathyamangalam, Tamil Nadu, India. Electronic address:

Development of potential sensors is inevitable for the detection of environmental pollutants including toxins, organic pollutants and heavy metal which cause hazardous effect to human and other living organisms. The present study is to develop silver nanoparticle (Ag NPs) based sensor for the accurate, sensitive and selective colorimetric detection of Hg ions from aqueous samples at nano molar level. The nanoparticles were synthesized chemically and it was stabilized by polyvinylpyrrolidone (PVP). The prepared particles were characterized by UV-visible spectroscopy, scanning electron microscopy (SEM), particle analysiser and Zetasizer. The UV-visible spectra of Ag NPs showed absorbance maximum at 392 nm. The average diameter of Ag NPs was determined to be 6 ± 0.9 nm by using particle analyzer. The zeta sizer analysis showed that the PVP stabilized Ag NPs possessed a zeta potential of -35.56 ± 3 mV. The Ag NPs-methionine conjugate showed the colour change from the brownish yellow colour to colourless when it was reacted with mercury. The Ag NPs conjugated methionine is sensitive to mercury and detects the mercury at nano molar level. The influence of other metal ion did not interfere with the detection and quantification of Hg. The detection of Hg was also performed with paper strip and agarose gel method. The Ag NPs conjugate with methionine can applied for the detection of Hg from various aqueous samples.
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http://dx.doi.org/10.1016/j.saa.2019.117712DOI Listing
March 2020
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