Deepak Balram | National Taipei University of Technology (original) (raw)

Papers by Deepak Balram

Research paper thumbnail of Silver doped dodecahedral metal-organic framework anchored RGO nanosheets for nanomolar quantification of priority toxic pollutant in aquatic environment

Journal of Alloys and Compounds

Research paper thumbnail of Nanomolar detection of food additive tert-butylhydroquinone in edible oils based on novel ternary metal oxide embedded β-cyclodextrin functionalized carbon black

Food Chemistry, May 1, 2022

It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In thi... more It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In this work, we report the sensitive electrochemical detection of widely used cytotoxic food preservative tert-butylhydroquinone (TBHQ). A novel nanocomposite was sonochemically prepared by embedding ternary metal oxide (TMO) comprising ZnO, CuO, and MgO in β-cyclodextrin (β-CD) functionalized carbon black (CB). The properties of the prepared nanocomposite were evaluated by employing multiple characterization methods. The nanocomposite fabricated on a screen printed carbon electrode exhibited exceptional electrocatalytic activity towards TBHQ detection, evident from the resultant very low detection limit of 1 nM and high sensitivity of 22.67 μA μM-1 cm-2. Moreover, the developed TBHQ sensor evinced all the important traits of a good electrochemical sensor including excellent selectivity, stability, reproducibility, and repeatability. Furthermore, for validating practical feasibility of TBHQ detection, we successfully determined this food additive in edible oils.

Research paper thumbnail of A sensitive and economical electrochemical platform for detection of food additive tert-butylhydroquinone based on porous Co3O4 nanorods embellished chemically oxidized carbon black

Research paper thumbnail of Functionalization of CNFs surface with β-cyclodextrin and decoration of hematite nanoparticles for detection and degradation of toxic fungicide carbendazim

Applied Surface Science, 2022

Research paper thumbnail of Nanomolar detection of food additive tert-butylhydroquinone in edible oils based on novel ternary metal oxide embedded β-cyclodextrin functionalized carbon black

Food Chemistry, 2021

It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In thi... more It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In this work, we report the sensitive electrochemical detection of widely used cytotoxic food preservative tert-butylhydroquinone (TBHQ). A novel nanocomposite was sonochemically prepared by embedding ternary metal oxide (TMO) comprising ZnO, CuO, and MgO in β-cyclodextrin (β-CD) functionalized carbon black (CB). The properties of the prepared nanocomposite were evaluated by employing multiple characterization methods. The nanocomposite fabricated on a screen printed carbon electrode exhibited exceptional electrocatalytic activity towards TBHQ detection, evident from the resultant very low detection limit of 1 nM and high sensitivity of 22.67 μA μM-1 cm-2. Moreover, the developed TBHQ sensor evinced all the important traits of a good electrochemical sensor including excellent selectivity, stability, reproducibility, and repeatability. Furthermore, for validating practical feasibility of TBHQ detection, we successfully determined this food additive in edible oils.

Research paper thumbnail of Significance of implementing polarity detection circuits in audio preamplifiers

2015 International Conference on Advances in Computing, Communications and Informatics (ICACCI), 2015

The reversal of the current directions in audio circuit elements causes polarity inversion of the... more The reversal of the current directions in audio circuit elements causes polarity inversion of the acquired audio signal with respect to the reference input signal. The objective of the work presented in this paper is to implement a simple polarity detection circuit in audio preamplifiers which provides an indication of the signal polarity inversion. The present work also demonstrates the possibilities of polarity inversion in audio circuits of audio data acquisition devices. Inputs fed in the inverting/noninverting terminals of audio operational amplifiers (Op-Amps) cause polarity reversal of the amplitude values of the speech/audio signals. Even though, polarity inversion in audio circuits are perceptually indistinguishable, provides inaccurate values of speech parameters estimated by processing the speech. The work presented in this paper discusses, how polarity inversion is introduced at the circuit level and proposes a polarity detection circuit which provides an indication of polarity reversal after the pre amplification. The effectiveness of the proposed polarity inversion circuit is confirmed by 100 % polarity detection rate for the 100 randomly selected audio files of the CMU-Arctic database when simulated using Proteus 8.0. The paper is concluded by discussing the significance of VLSI implementation proposed polarity detection circuit in the most commonly used audio preamplifier systems.

Research paper thumbnail of Ultrasensitive detection of food colorant sunset yellow using nickel nanoparticles promoted lettuce-like spinel Co3O4 anchored GO nanosheets

Food and Chemical Toxicology, 2021

Synthetic food colorants are extensively used across the globe regardless of the fact that they i... more Synthetic food colorants are extensively used across the globe regardless of the fact that they induce deleterious side effects when used in higher amounts. In this work, a novel electrochemical sensor based on nickel nanoparticles doped lettuce-like Co3O4 anchored graphene oxide (GO) nanosheets was developed for effective detection of sulfonated azo dye sunset yellow widely used as a food colorant. Hydrothermal synthesis was adopted for the preparation of lettuce-like spinel Co3O4 nanoparticles and Ni-Co3O4 NPs/GO nanocomposite was prepared using ecofriendly and economical sonochemical method. The prepared ternary nanocomposite meticulously fabricated on a screen-printed carbon electrode exhibited remarkable electrocatalytic activity towards sunset yellow determination. This is apparent from the resultant well-defined and intense redox peak currents of Ni-Co3O4 NPs/GO nanocomposite modified electrode at very low potentials. The developed sunset yellow sensor exhibited a high sensitivity of 4.16 μA μM-1 cm-2 and a nanomolar detection limit of 0.9 nM in the linear range 0.125-108.5 μM. Furthermore, experiments were conducted to affirm excellent stability, reproducibility, repeatability, and selectivity of proposed sensor. The practicality of sunset yellow determination using the developed sensor was analyzed in different varieties of food samples including jelly, soft drink, ice cream, and candy resulting in recovery in the range of 96.16%-102.56%.

Research paper thumbnail of Bi-functional renewable biopolymer wrapped CNFs/Ag doped spinel cobalt oxide as a sensitive platform for highly toxic nitroaromatic compound detection and degradation

Chemosphere, 2021

Nanomolar-level detection of priority toxic pollutant 4-nitrophenol (4-NP) in environment using a... more Nanomolar-level detection of priority toxic pollutant 4-nitrophenol (4-NP) in environment using a novel ternary nanocomposite based electrochemical sensor and its photocatalytic degradation is reported in this paper. A non-toxic and renewable natural biopolymer, chitosan wrapped carbon nanofibers was embedded with Ag doped spinel Co3O4 to prepare the bi-functional ternary nanocomposite. Economical and ecofriendly sonochemical method was employed in preparation of this porous nanocomposite. We used one-pot aqueous solution approach to synthesize Ag-Co3O4 nanoflowers and ultrasound-assisted method was utilized to prepare CS-CNFs. Morphological and structural properties of synthesized materials were analyzed using different characterization techniques. Electrochemical investigations using cyclic voltammetry and differential pulse voltammetry carried out with prepared ternary nanocomposite modified carbon electrode revealed its outstanding electrocatalytic activity in 4-NP quantification. The developed 4-NP sensor showcased excellent sensitivity of 55.98 μAμM-1cm-2 and nanomolar detection limit of 0.4 nM. Moreover, reproducibility, repeatability, stability, and selectivity were evaluated to confirm reliability of developed sensor. Further, real sample analyses were conducted using domestic sewage, underground water, and tomato to affirm the practical feasibility of 4-NP detection using the proposed sensor.

Research paper thumbnail of A novel soft sensor based warning system for hazardous ground-level ozone using advanced damped least squares neural network

Ecotoxicology and Environmental Safety, 2020

Estimation of hazardous air pollutants in the urban environment for maintaining public safety is ... more Estimation of hazardous air pollutants in the urban environment for maintaining public safety is a significant concern to mankind. In this paper, we have developed an efficient air quality warning system based on a low-cost and robust ground-level ozone soft sensor. The soft sensor was developed based on a novel technique of damped least squares neural network (DLSNN) with greedy backward elimination (GBE) for the estimation of hazardous ground-level ozone. Only three meteorological factors were used as input variables in the estimation of groundlevel ozone and we have used weighted k-nearest neighbors (WkNN) classifier with fast response for development of air quality warning system. We have chosen the urban areas of Taiwan for this study and have analyzed seasonal variations in the ground-level ozone concentration of various cities in Taiwan as part of this work. Moreover, descriptive statistics and linear dependence of ozone concentration based on Spearman correlation coefficient, Kendall's tau coefficient, and Pearson coefficient are calculated. The proposed DLSNN/GBE method exhibited excellent performance resulting in very low mean square error (MSE), mean absolute error (MAE), and high coefficient of determination (R 2) compared to other traditional approaches in ozone concentration estimation. We have achieved a good fit in the determination of ozone concentration from meteorological features of atmosphere. Moreover, the excellent performance of proposed urban air quality warning system was evident from the good F1-score value of 0.952 achieved by the WkNN classifier.

Research paper thumbnail of Morphological evolution of nanosheets-stacked spherical ZnO for preparation of GO-Zn/ZnO ternary nanocomposite: A novel electrochemical platform for nanomolar detection of antihistamine promethazine hydrochloride

Journal of Alloys and Compounds, 2021

Abstract This work focuses on the nanomolar-level detection of the antihistamine, promethazine hy... more Abstract This work focuses on the nanomolar-level detection of the antihistamine, promethazine hydrochloride (PMTZ), based on a novel ternary nanocomposite sonochemically prepared using a zinc-graphene oxide (GO-Zn) complex and a nanosheets-stacked spherical ZnO. The efficient detection of PMTZ is very important because of its critical side effects when overdosed and its high toxicity to aquatic life. Morphologically varied ZnO nanostructures (spindle-like, nanosheets-stacked spherical, nanoplates-based spherical, and rod-flower) were synthesized using a new aqueous solution approach by regulating the concentration of base in the reaction mixture. Characterization techniques including SEM, TEM, elemental mapping, XRD, Raman spectroscopy, and XPS were utilized for analyzing the properties of synthesized materials. Electrochemical investigations employing cyclic voltammetry and differential pulse voltammetry techniques showcased outstanding electrocatalytic activity of the proposed ternary nanocomposite-modified screen-printed carbon electrode towards PMTZ detection. The PMTZ sensor attained ultra-low detection limit of 0.3 nM, broad linear range from 0.05 to 177.45 µM, and a sensitivity of 5.29 µAµM−1cm−2. Furthermore, good operational stability, anti-interference, repeatability, and reproducibility was exhibited by the developed sensor. The real sample analysis provided excellent recovery results indicating outstanding practicability of PMTZ detection.

Research paper thumbnail of Surface functionalization of CNTs with amine group and decoration of begonia-like ZnO for detection of antipyretic drug acetaminophen

Applied Surface Science, 2021

Abstract Detection of hepatotoxic antipyretic drug acetaminophen (APAP) at nanomolar level is det... more Abstract Detection of hepatotoxic antipyretic drug acetaminophen (APAP) at nanomolar level is detailed in this paper. We have prepared a novel nanocomposite with excellent electrocatalytic property for the detection of APAP based on amine-functionalized multi-walled carbon nanotubes (NH2-MWCNTs) decorated zinc oxide (ZnO). Surface functionalization of carbon nanotubes with amine group using ultrasound-assisted approach and synthesis of begonia flower-like ZnO nanoparticles based on arginine-assisted aqueous solution method were performed. Techniques including UV-Vis, micro Raman spectroscopy, FTIR, XRD, elemental mapping, and SEM were used to record significant characterizations of synthesized materials for analysis. The outstanding surface controlled electrocatalysis of APAP at ZnO NPs/NH2-MWCNTs modified SPCE was evident from the well-defined redox peak currents observed at low potentials during electrochemical investigations. Moreover, the resultant ultra-low detection limit of 1 nM and very high sensitivity of 89.64 μA μM−1 cm−2 showcase the excellent performance of proposed APAP sensor. We have investigated all the salient features of the APAP sensor as part of this work and it exhibited good stability, reproducibility, repeatability, and excellent anti-interference property. The practical feasibility of APAP detection was also evaluated by conducting experiment on real samples including APAP tablet, human urine, and human serum.

Research paper thumbnail of Ultrasensitive detection of cytotoxic food preservative tert-butylhydroquinone using 3D cupric oxide nanoflowers embedded functionalized carbon nanotubes

Journal of Hazardous Materials, 2021

a n d Rasana N, Ultrasensitive detection of cytotoxic food preservative tertbutylhydroquinone usi... more a n d Rasana N, Ultrasensitive detection of cytotoxic food preservative tertbutylhydroquinone using 3D cupric oxide nanoflowers embedded functionalized carbon nanotubes,

Research paper thumbnail of Ultrasensitive Electrochemical Detection and Plasmon-Enhanced Photocatalytic Degradation of Rhodamine B Based on Dual-Functional, 3D, Hierarchical Ag/ZnO Nanoflowers

Sensors

The sensitive detection and degradation of synthetic dyes are pivotal to maintain safety owing to... more The sensitive detection and degradation of synthetic dyes are pivotal to maintain safety owing to the adverse side effects they impart on living beings. In this work, we developed a sensitive electrochemical sensor for the nanomolar-level detection of rhodamine B (RhB) using a dual-functional, silver-decorated zinc oxide (Ag/ZnO) composite-modified, screen-printed carbon electrode. The plasmon-enhanced photocatalytic degradation of organic pollutant RhB was also performed using this nanocomposite prepared by embedding different weight percentages (1, 3, and 5 wt%) of Ag nanoparticles on the surface of a three-dimensional (3D), hierarchical ZnO nanostructure based on the photoreduction approach. The structure and morphology of an Ag/ZnO nanocomposite were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), elemental mapping, ultraviolet-visible (UV-vis) spectroscopy, and X-ray diffraction (XRD). The electrochemical sensor exhibited a very high...

Research paper thumbnail of Synthesis of amine-functionalized multi-walled carbon nanotube/3D rose flower-like zinc oxide nanocomposite for sensitive electrochemical detection of flavonoid morin

Research paper thumbnail of Sonochemical synthesis of iron-graphene oxide/honeycomb-like ZnO ternary nanohybrids for sensitive electrochemical detection of antipsychotic drug chlorpromazine

Ultrasonics Sonochemistry

Research paper thumbnail of Air quality warning system based on a localized PM2.5 soft sensor using a novel approach of Bayesian regularized neural network via forward feature selection

Ecotoxicology and Environmental Safety, 2019

It is highly significant to develop efficient soft sensors to estimate the concentration of hazar... more It is highly significant to develop efficient soft sensors to estimate the concentration of hazardous pollutants in a region to maintain environmental safety. In this paper, an air quality warning system based on a robust PM2.5 soft sensor and support vector machine (SVM) classifier is reported. The soft sensor for the estimation of PM2.5 concentration is proposed using a novel approach of Bayesian regularized neural network (BRNN) via forward feature selection (FFS). Zuoying district of Taiwan is selected as the region of study for implementation of the estimation system because of the high pollution in the region. Descriptive statistics of various pollutants in Zuoying district is computed as part of the study. Moreover, seasonal variation of particulate matter (PM) concentration is analyzed to evaluate the impact of various seasons on the increased levels of PM in the region. To investigate the linear dependence of concentration of different pollutants to the concentration of PM2.5, Pearson correlation coefficient, Kendall's tau coefficient, and Spearman coefficient are computed. To achieve high performance for the PM2.5 estimation, selection of appropriate forward features from the input variables is carried out using FFS technique and Bayesian regularization is incorporated to the neural network system to avoid the overfitting problem. The comparative evaluation of performance of BRNN/FFS estimation system with various other methods shows that our proposed estimation system has the lowest mean square error (MSE), root mean square error (RMSE), and mean absolute error (MAE). Moreover, the coefficient of determination (R-squared) is around 0.95 for the proposed estimation method, which denotes a good fit. Evaluation of the SVM classifier showed good performance indicating that the proposed air quality warning system is efficient.

Research paper thumbnail of Ecofriendly Synthesized Reduced Graphene Oxide Embellished Marsh Marigold-like Zinc Oxide Nanocomposite Based on Ultrasonication Technique for the Sensitive Detection of Environmental Pollutant Hydroquinone

Ultrasonics Sonochemistry

Research paper thumbnail of A Novel Electrochemical Sensor Based on Flower Shaped Zinc Oxide Nanoparticles for the Efficient Detection of Dopamine

International Journal of Electrochemical Science

Research paper thumbnail of Synthesis of a functionalized multi-walled carbon nanotube decorated ruskin michelle-like ZnO nanocomposite and its application in the development of a highly sensitive hydroquinone sensor

Inorganic Chemistry Frontiers

Electrochemical determination of hydroquinone based on a f-MWCNT decorated ruskin michelle-like Z... more Electrochemical determination of hydroquinone based on a f-MWCNT decorated ruskin michelle-like ZnO nanocomposite.

Research paper thumbnail of Electrochemical Detection of Antibiotic Drug Chloramphenicol Based on Graphene Oxide/Hierarchical Zinc Oxide Nanocomposite

Inorganic Chemistry Frontiers

A novel electrochemical sensor based on a graphene oxide (GO)/three-dimensional (3D) hierarchical... more A novel electrochemical sensor based on a graphene oxide (GO)/three-dimensional (3D) hierarchical zinc oxide (ZnO) nanocomposite was developed for the efficient determination of the antibiotic drug chloramphenicol (CAP). The hierarchical...

Research paper thumbnail of Silver doped dodecahedral metal-organic framework anchored RGO nanosheets for nanomolar quantification of priority toxic pollutant in aquatic environment

Journal of Alloys and Compounds

Research paper thumbnail of Nanomolar detection of food additive tert-butylhydroquinone in edible oils based on novel ternary metal oxide embedded β-cyclodextrin functionalized carbon black

Food Chemistry, May 1, 2022

It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In thi... more It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In this work, we report the sensitive electrochemical detection of widely used cytotoxic food preservative tert-butylhydroquinone (TBHQ). A novel nanocomposite was sonochemically prepared by embedding ternary metal oxide (TMO) comprising ZnO, CuO, and MgO in β-cyclodextrin (β-CD) functionalized carbon black (CB). The properties of the prepared nanocomposite were evaluated by employing multiple characterization methods. The nanocomposite fabricated on a screen printed carbon electrode exhibited exceptional electrocatalytic activity towards TBHQ detection, evident from the resultant very low detection limit of 1 nM and high sensitivity of 22.67 μA μM-1 cm-2. Moreover, the developed TBHQ sensor evinced all the important traits of a good electrochemical sensor including excellent selectivity, stability, reproducibility, and repeatability. Furthermore, for validating practical feasibility of TBHQ detection, we successfully determined this food additive in edible oils.

Research paper thumbnail of A sensitive and economical electrochemical platform for detection of food additive tert-butylhydroquinone based on porous Co3O4 nanorods embellished chemically oxidized carbon black

Research paper thumbnail of Functionalization of CNFs surface with β-cyclodextrin and decoration of hematite nanoparticles for detection and degradation of toxic fungicide carbendazim

Applied Surface Science, 2022

Research paper thumbnail of Nanomolar detection of food additive tert-butylhydroquinone in edible oils based on novel ternary metal oxide embedded β-cyclodextrin functionalized carbon black

Food Chemistry, 2021

It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In thi... more It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In this work, we report the sensitive electrochemical detection of widely used cytotoxic food preservative tert-butylhydroquinone (TBHQ). A novel nanocomposite was sonochemically prepared by embedding ternary metal oxide (TMO) comprising ZnO, CuO, and MgO in β-cyclodextrin (β-CD) functionalized carbon black (CB). The properties of the prepared nanocomposite were evaluated by employing multiple characterization methods. The nanocomposite fabricated on a screen printed carbon electrode exhibited exceptional electrocatalytic activity towards TBHQ detection, evident from the resultant very low detection limit of 1 nM and high sensitivity of 22.67 μA μM-1 cm-2. Moreover, the developed TBHQ sensor evinced all the important traits of a good electrochemical sensor including excellent selectivity, stability, reproducibility, and repeatability. Furthermore, for validating practical feasibility of TBHQ detection, we successfully determined this food additive in edible oils.

Research paper thumbnail of Significance of implementing polarity detection circuits in audio preamplifiers

2015 International Conference on Advances in Computing, Communications and Informatics (ICACCI), 2015

The reversal of the current directions in audio circuit elements causes polarity inversion of the... more The reversal of the current directions in audio circuit elements causes polarity inversion of the acquired audio signal with respect to the reference input signal. The objective of the work presented in this paper is to implement a simple polarity detection circuit in audio preamplifiers which provides an indication of the signal polarity inversion. The present work also demonstrates the possibilities of polarity inversion in audio circuits of audio data acquisition devices. Inputs fed in the inverting/noninverting terminals of audio operational amplifiers (Op-Amps) cause polarity reversal of the amplitude values of the speech/audio signals. Even though, polarity inversion in audio circuits are perceptually indistinguishable, provides inaccurate values of speech parameters estimated by processing the speech. The work presented in this paper discusses, how polarity inversion is introduced at the circuit level and proposes a polarity detection circuit which provides an indication of polarity reversal after the pre amplification. The effectiveness of the proposed polarity inversion circuit is confirmed by 100 % polarity detection rate for the 100 randomly selected audio files of the CMU-Arctic database when simulated using Proteus 8.0. The paper is concluded by discussing the significance of VLSI implementation proposed polarity detection circuit in the most commonly used audio preamplifier systems.

Research paper thumbnail of Ultrasensitive detection of food colorant sunset yellow using nickel nanoparticles promoted lettuce-like spinel Co3O4 anchored GO nanosheets

Food and Chemical Toxicology, 2021

Synthetic food colorants are extensively used across the globe regardless of the fact that they i... more Synthetic food colorants are extensively used across the globe regardless of the fact that they induce deleterious side effects when used in higher amounts. In this work, a novel electrochemical sensor based on nickel nanoparticles doped lettuce-like Co3O4 anchored graphene oxide (GO) nanosheets was developed for effective detection of sulfonated azo dye sunset yellow widely used as a food colorant. Hydrothermal synthesis was adopted for the preparation of lettuce-like spinel Co3O4 nanoparticles and Ni-Co3O4 NPs/GO nanocomposite was prepared using ecofriendly and economical sonochemical method. The prepared ternary nanocomposite meticulously fabricated on a screen-printed carbon electrode exhibited remarkable electrocatalytic activity towards sunset yellow determination. This is apparent from the resultant well-defined and intense redox peak currents of Ni-Co3O4 NPs/GO nanocomposite modified electrode at very low potentials. The developed sunset yellow sensor exhibited a high sensitivity of 4.16 μA μM-1 cm-2 and a nanomolar detection limit of 0.9 nM in the linear range 0.125-108.5 μM. Furthermore, experiments were conducted to affirm excellent stability, reproducibility, repeatability, and selectivity of proposed sensor. The practicality of sunset yellow determination using the developed sensor was analyzed in different varieties of food samples including jelly, soft drink, ice cream, and candy resulting in recovery in the range of 96.16%-102.56%.

Research paper thumbnail of Bi-functional renewable biopolymer wrapped CNFs/Ag doped spinel cobalt oxide as a sensitive platform for highly toxic nitroaromatic compound detection and degradation

Chemosphere, 2021

Nanomolar-level detection of priority toxic pollutant 4-nitrophenol (4-NP) in environment using a... more Nanomolar-level detection of priority toxic pollutant 4-nitrophenol (4-NP) in environment using a novel ternary nanocomposite based electrochemical sensor and its photocatalytic degradation is reported in this paper. A non-toxic and renewable natural biopolymer, chitosan wrapped carbon nanofibers was embedded with Ag doped spinel Co3O4 to prepare the bi-functional ternary nanocomposite. Economical and ecofriendly sonochemical method was employed in preparation of this porous nanocomposite. We used one-pot aqueous solution approach to synthesize Ag-Co3O4 nanoflowers and ultrasound-assisted method was utilized to prepare CS-CNFs. Morphological and structural properties of synthesized materials were analyzed using different characterization techniques. Electrochemical investigations using cyclic voltammetry and differential pulse voltammetry carried out with prepared ternary nanocomposite modified carbon electrode revealed its outstanding electrocatalytic activity in 4-NP quantification. The developed 4-NP sensor showcased excellent sensitivity of 55.98 μAμM-1cm-2 and nanomolar detection limit of 0.4 nM. Moreover, reproducibility, repeatability, stability, and selectivity were evaluated to confirm reliability of developed sensor. Further, real sample analyses were conducted using domestic sewage, underground water, and tomato to affirm the practical feasibility of 4-NP detection using the proposed sensor.

Research paper thumbnail of A novel soft sensor based warning system for hazardous ground-level ozone using advanced damped least squares neural network

Ecotoxicology and Environmental Safety, 2020

Estimation of hazardous air pollutants in the urban environment for maintaining public safety is ... more Estimation of hazardous air pollutants in the urban environment for maintaining public safety is a significant concern to mankind. In this paper, we have developed an efficient air quality warning system based on a low-cost and robust ground-level ozone soft sensor. The soft sensor was developed based on a novel technique of damped least squares neural network (DLSNN) with greedy backward elimination (GBE) for the estimation of hazardous ground-level ozone. Only three meteorological factors were used as input variables in the estimation of groundlevel ozone and we have used weighted k-nearest neighbors (WkNN) classifier with fast response for development of air quality warning system. We have chosen the urban areas of Taiwan for this study and have analyzed seasonal variations in the ground-level ozone concentration of various cities in Taiwan as part of this work. Moreover, descriptive statistics and linear dependence of ozone concentration based on Spearman correlation coefficient, Kendall's tau coefficient, and Pearson coefficient are calculated. The proposed DLSNN/GBE method exhibited excellent performance resulting in very low mean square error (MSE), mean absolute error (MAE), and high coefficient of determination (R 2) compared to other traditional approaches in ozone concentration estimation. We have achieved a good fit in the determination of ozone concentration from meteorological features of atmosphere. Moreover, the excellent performance of proposed urban air quality warning system was evident from the good F1-score value of 0.952 achieved by the WkNN classifier.

Research paper thumbnail of Morphological evolution of nanosheets-stacked spherical ZnO for preparation of GO-Zn/ZnO ternary nanocomposite: A novel electrochemical platform for nanomolar detection of antihistamine promethazine hydrochloride

Journal of Alloys and Compounds, 2021

Abstract This work focuses on the nanomolar-level detection of the antihistamine, promethazine hy... more Abstract This work focuses on the nanomolar-level detection of the antihistamine, promethazine hydrochloride (PMTZ), based on a novel ternary nanocomposite sonochemically prepared using a zinc-graphene oxide (GO-Zn) complex and a nanosheets-stacked spherical ZnO. The efficient detection of PMTZ is very important because of its critical side effects when overdosed and its high toxicity to aquatic life. Morphologically varied ZnO nanostructures (spindle-like, nanosheets-stacked spherical, nanoplates-based spherical, and rod-flower) were synthesized using a new aqueous solution approach by regulating the concentration of base in the reaction mixture. Characterization techniques including SEM, TEM, elemental mapping, XRD, Raman spectroscopy, and XPS were utilized for analyzing the properties of synthesized materials. Electrochemical investigations employing cyclic voltammetry and differential pulse voltammetry techniques showcased outstanding electrocatalytic activity of the proposed ternary nanocomposite-modified screen-printed carbon electrode towards PMTZ detection. The PMTZ sensor attained ultra-low detection limit of 0.3 nM, broad linear range from 0.05 to 177.45 µM, and a sensitivity of 5.29 µAµM−1cm−2. Furthermore, good operational stability, anti-interference, repeatability, and reproducibility was exhibited by the developed sensor. The real sample analysis provided excellent recovery results indicating outstanding practicability of PMTZ detection.

Research paper thumbnail of Surface functionalization of CNTs with amine group and decoration of begonia-like ZnO for detection of antipyretic drug acetaminophen

Applied Surface Science, 2021

Abstract Detection of hepatotoxic antipyretic drug acetaminophen (APAP) at nanomolar level is det... more Abstract Detection of hepatotoxic antipyretic drug acetaminophen (APAP) at nanomolar level is detailed in this paper. We have prepared a novel nanocomposite with excellent electrocatalytic property for the detection of APAP based on amine-functionalized multi-walled carbon nanotubes (NH2-MWCNTs) decorated zinc oxide (ZnO). Surface functionalization of carbon nanotubes with amine group using ultrasound-assisted approach and synthesis of begonia flower-like ZnO nanoparticles based on arginine-assisted aqueous solution method were performed. Techniques including UV-Vis, micro Raman spectroscopy, FTIR, XRD, elemental mapping, and SEM were used to record significant characterizations of synthesized materials for analysis. The outstanding surface controlled electrocatalysis of APAP at ZnO NPs/NH2-MWCNTs modified SPCE was evident from the well-defined redox peak currents observed at low potentials during electrochemical investigations. Moreover, the resultant ultra-low detection limit of 1 nM and very high sensitivity of 89.64 μA μM−1 cm−2 showcase the excellent performance of proposed APAP sensor. We have investigated all the salient features of the APAP sensor as part of this work and it exhibited good stability, reproducibility, repeatability, and excellent anti-interference property. The practical feasibility of APAP detection was also evaluated by conducting experiment on real samples including APAP tablet, human urine, and human serum.

Research paper thumbnail of Ultrasensitive detection of cytotoxic food preservative tert-butylhydroquinone using 3D cupric oxide nanoflowers embedded functionalized carbon nanotubes

Journal of Hazardous Materials, 2021

a n d Rasana N, Ultrasensitive detection of cytotoxic food preservative tertbutylhydroquinone usi... more a n d Rasana N, Ultrasensitive detection of cytotoxic food preservative tertbutylhydroquinone using 3D cupric oxide nanoflowers embedded functionalized carbon nanotubes,

Research paper thumbnail of Ultrasensitive Electrochemical Detection and Plasmon-Enhanced Photocatalytic Degradation of Rhodamine B Based on Dual-Functional, 3D, Hierarchical Ag/ZnO Nanoflowers

Sensors

The sensitive detection and degradation of synthetic dyes are pivotal to maintain safety owing to... more The sensitive detection and degradation of synthetic dyes are pivotal to maintain safety owing to the adverse side effects they impart on living beings. In this work, we developed a sensitive electrochemical sensor for the nanomolar-level detection of rhodamine B (RhB) using a dual-functional, silver-decorated zinc oxide (Ag/ZnO) composite-modified, screen-printed carbon electrode. The plasmon-enhanced photocatalytic degradation of organic pollutant RhB was also performed using this nanocomposite prepared by embedding different weight percentages (1, 3, and 5 wt%) of Ag nanoparticles on the surface of a three-dimensional (3D), hierarchical ZnO nanostructure based on the photoreduction approach. The structure and morphology of an Ag/ZnO nanocomposite were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), elemental mapping, ultraviolet-visible (UV-vis) spectroscopy, and X-ray diffraction (XRD). The electrochemical sensor exhibited a very high...

Research paper thumbnail of Synthesis of amine-functionalized multi-walled carbon nanotube/3D rose flower-like zinc oxide nanocomposite for sensitive electrochemical detection of flavonoid morin

Research paper thumbnail of Sonochemical synthesis of iron-graphene oxide/honeycomb-like ZnO ternary nanohybrids for sensitive electrochemical detection of antipsychotic drug chlorpromazine

Ultrasonics Sonochemistry

Research paper thumbnail of Air quality warning system based on a localized PM2.5 soft sensor using a novel approach of Bayesian regularized neural network via forward feature selection

Ecotoxicology and Environmental Safety, 2019

It is highly significant to develop efficient soft sensors to estimate the concentration of hazar... more It is highly significant to develop efficient soft sensors to estimate the concentration of hazardous pollutants in a region to maintain environmental safety. In this paper, an air quality warning system based on a robust PM2.5 soft sensor and support vector machine (SVM) classifier is reported. The soft sensor for the estimation of PM2.5 concentration is proposed using a novel approach of Bayesian regularized neural network (BRNN) via forward feature selection (FFS). Zuoying district of Taiwan is selected as the region of study for implementation of the estimation system because of the high pollution in the region. Descriptive statistics of various pollutants in Zuoying district is computed as part of the study. Moreover, seasonal variation of particulate matter (PM) concentration is analyzed to evaluate the impact of various seasons on the increased levels of PM in the region. To investigate the linear dependence of concentration of different pollutants to the concentration of PM2.5, Pearson correlation coefficient, Kendall's tau coefficient, and Spearman coefficient are computed. To achieve high performance for the PM2.5 estimation, selection of appropriate forward features from the input variables is carried out using FFS technique and Bayesian regularization is incorporated to the neural network system to avoid the overfitting problem. The comparative evaluation of performance of BRNN/FFS estimation system with various other methods shows that our proposed estimation system has the lowest mean square error (MSE), root mean square error (RMSE), and mean absolute error (MAE). Moreover, the coefficient of determination (R-squared) is around 0.95 for the proposed estimation method, which denotes a good fit. Evaluation of the SVM classifier showed good performance indicating that the proposed air quality warning system is efficient.

Research paper thumbnail of Ecofriendly Synthesized Reduced Graphene Oxide Embellished Marsh Marigold-like Zinc Oxide Nanocomposite Based on Ultrasonication Technique for the Sensitive Detection of Environmental Pollutant Hydroquinone

Ultrasonics Sonochemistry

Research paper thumbnail of A Novel Electrochemical Sensor Based on Flower Shaped Zinc Oxide Nanoparticles for the Efficient Detection of Dopamine

International Journal of Electrochemical Science

Research paper thumbnail of Synthesis of a functionalized multi-walled carbon nanotube decorated ruskin michelle-like ZnO nanocomposite and its application in the development of a highly sensitive hydroquinone sensor

Inorganic Chemistry Frontiers

Electrochemical determination of hydroquinone based on a f-MWCNT decorated ruskin michelle-like Z... more Electrochemical determination of hydroquinone based on a f-MWCNT decorated ruskin michelle-like ZnO nanocomposite.

Research paper thumbnail of Electrochemical Detection of Antibiotic Drug Chloramphenicol Based on Graphene Oxide/Hierarchical Zinc Oxide Nanocomposite

Inorganic Chemistry Frontiers

A novel electrochemical sensor based on a graphene oxide (GO)/three-dimensional (3D) hierarchical... more A novel electrochemical sensor based on a graphene oxide (GO)/three-dimensional (3D) hierarchical zinc oxide (ZnO) nanocomposite was developed for the efficient determination of the antibiotic drug chloramphenicol (CAP). The hierarchical...