There is a growing fascination with electrochemical sensors designed for detecting microplastics and/or nanoplastics (MPs/NPs). Among the various methods available, the electrochemical approach stands out for its numerous advantages. These advantages include potential energy efficiency, monitoring, and diagnostic capabilities, low-temperature and low-pressure operation, versatility, scalability, selectivity, and environmental friendliness. In particular, the focus is on exploring changes in electrochemical properties to study the interaction between MPs and electrodes. This chapter briefly explains MPs contamination with its impact and discusses the MPs detection with electrochemical techniques. Several recent examples of such techniques are presented, including electrochemical impedance spectroscopy in combination with flow cytometry, chronoamperometry, and voltammetry. Finally, this chapter extensively explores the existing challenges encountered in electrochemical sensing of MPs in diverse environmental samples. It also highlights the potential opportunities in this field, paving the way for further advancements in the identification and monitoring of MPs/NPs in our environment. The goal is to enhance our understanding and ability to detect these harmful pollutants effectively.

Carbaryl and carbofuran are the carbamate pesticides which have been widely used worldwide to control insects in crops and house. If the pesticides entered in to the food products and drinking water, they could cause serious health effects in humans. Therefore, the development of a rapid, simple, sensitive and selective analytical device for on-site detection of carbamates is crucial to evaluate food and environmental samples. Recently, semiconducting single-walled carbon nanotube-based field effect transistors (s-SWCNT/FETs) have shown several advantages such as high carrier mobility, good on/off ratio, quasi ballistic electron transport, label-free detection and real-time response. Herein, cobalt ferrite (CFO) nanoparticles decorated s-SWCNTs have been prepared and used to bridge the source and drain electrodes. As-prepared CFO/s-SWCNT/FET had been used for the nonenzymatic detection of carbaryl and carbofuran. When used as a sensing platform, the CFO/s-SWCNT hybrid film exhibited high sensitivity, and selectivity with a wide linear range of detection from 10 to 100 fMand the lowest limit of detections for carbaryl (0.11 fM) and carbofuran (0.07 fM) were estimated. This sensor was also used to detect carbaryl in tomato and cabbage samples, which confirmed its practical acceptance. Such performance may be attributed to the oxidation of carbamates by potent catalytic activity of CFO, which led to the changes in the charge transfer reaction on the s-SWCNTs/FET conduction channel. This work presents a novel CFO/s-SWCNT based sensing system which could be used to quantify pesticide residues in food samples.

RNA isolation and amplification-free user-friendly detection of SARS-CoV-2 is the need of hour especially at resource limited settings. Herein, we devised the peptides of human angiotensin converting enzyme-2 (hACE-2) as bioreceptor at electrode interface for selective targeting of receptor binding domains (RBD) of SARS-CoV-2 spike protein (SP). Disposable carbon-screen printed electrode modified with methylene blue (MB) electroadsorbed graphene oxide (GO) has been constructed as cost-efficient and scalable platform for hACE-2 peptide-based SARS-CoV-2 detection. In silico molecular docking of customized 25 mer peptides with RBD of SARS-CoV-2 SP were validated by AutoDock CrankPep. N-terminal region of ACE-2 showed higher binding affinity of -20.6 kcal/mol with 15 H-bond, 9 of which were <3 Å. Electrochemical biosensing of different concentrations of SPs were determined by cyclic voltammetry (CV) and chronoamperometry (CA), enabling limit of detection (LOD) 0.58 pg/mL and 0.71 pg/mL, respectively. MB-GO devised hACE-2 peptide platform exert an enhanced current sensitivity of 0.0105 mA/pg mL-1 cm-2 (R2 = 0.9792) (CV) and 0.45 nA/pg mL-1 (R2 = 0.9570) (CA) against SP in the range of 1 pg/mL to 1 µg/mL. For clinical feasibility, nasopharyngeal and oropharyngeal swab specimens in viral transport medium were directly tested with the prepared peptide biosensor and validated with RT-PCR, promising for point-of-need analysis.

Heavy metal toxicity (HMT) is a major threat to agriculture production and productivity worldwide; it affects the yield potential of the major food crops. It impairs the plant's physiological function, reduces seed germination, produces oxidative stress, and hinders the plant's photosynthetic ability. Plants absorb these heavy metals from the contaminated soils and cause severe health complications to those consuming the products grown out of the contaminated sites. The major contributor to HMT is human and human-related activities. Therefore, it is very important to address the HMT problem in agriculture. Agronomic interventions such as bioremediation using either plants (phytoremediation) or microbes (microbial bioremediation) is one of the effective methods to remove heavy metals from the soil. More than 400 plant species were reported as hyperaccumulators of various heavy metals. Breeders may develop heavy metal tolerant crop cultivars through breeding and biotechnological interventions for wider adaptation. Several heavy metal tolerant crop cultivars have been developed and commercialized for various economically important food crops. Leveraging omics, gene editing, and high throughput screening tools may speed up the cultivar development. Therefore, we focus on reviewing the agronomic, breeding, and biotechnological interventions to mitigate the HMT problem in agriculture, along with sensors for heavy metal detection to speed up the screening process.

Oxidation of mono and bimetallic nanoparticles have a profound impact in determining the catalytic activity. In the present work, copper and nickel bimetallics with three different weight ratios of 25:75, 50:50 and 75:25 synthesised by hydrothermal process, were oxidised at 400 degrees C for 1 hour in order to compare the effect on structure and catalytic properties with respect to pure metals (Ni and Cu). On oxidation, nickel only partially oxidised to nickel oxide while copper transformed to cupric oxide completely. Among all the samples, 75:25 showed a high catalytic activity with a good recyclability towards the reduction of 4-nitrophenol with a rate constant value of 4.89 x 10(-3) s(-1) which was found to be three times larger than CuO. An intense oxidation peak observed for 75:25 in cyclic voltammetry indicated more electron transfer between 4-nitrophenol and catalyst. The synergetic effect due to the presence of Cu and Ni at low nickel content enhanced the catalytic activity. The present study emphasises the significance of concentration dependent phase formation in bimetallics upon oxidation and its effect on catalytic activity. (C) 2019 Elsevier B.V. All rights reserved.

Semiconducting single-walled carbon nanotubes (s-SWCNTs) have been used in electrical transducers for environmental and health monitoring due to their quasi ballistic electron transport, efficient transconductance, high carrier mobility, good on/off ratio, excellent mechanical properties, etc. Herein, we have prepared a non-enzymatic pesticide sensor to selectively detect methyl parathion (MP, which is a restricted use pesticide according to the EPA) using a silver–zinc oxide (Ag–ZnO) composite decorated s-SWCNT based field-effect transistor (FET). The Ag–ZnO/s-SWCNT film is also characterized by using field-emission scanning electron microscopy (FE-SEM), energy-dispersive spectrometry (EDS), X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), ultraviolet-visible-near infrared (UV-vis-NIR), Raman and photoluminescence (PL) spectroscopies. The electrical response of the Ag–ZnO/s-SWCNT–FET was measured under ambient conditions in the presence and absence of MP. The hydrolysis of MP took place due to the potent catalytic activity of Ag–ZnO, which led to changes in transistor conductance. Based on this, detection of the different concentrations of MP was demonstrated by using Ag–ZnO/s-SWCNT–FET. The Ag–ZnO/s-SWCNT–FET device showed a linear response from 1 × 10−16 M to 1 × 10−4 M MP with a limit of detection (LOD) of 0.27 × 10−16 M in 0.1 M phosphate buffer solution (PBS). In addition, Ag–ZnO/s-SWCNT–FET exhibited acceptable reproducibility and repeatability when employed for MP detection. Moreover, the proposed FET sensor was highly stable under ambient conditions. Finally, the accurate detection of spiked MP is demonstrated in soil and rice samples with good recovery.

Semiconducting single-walled carbon nanotubes (s-SWCNTs) have been demonstrated as an excellent material for transistors, miniaturized devices and sensors due to their high carrier mobility, stability, scattering-free ballistic transport of carriers etc. Herein, we have designed a biosensor to selectively detect methyl parathion (MP, organophosphorus pesticide) using glutaraldehyde (Glu) cross-linked with acetylcholinesterase (AChE) immobilized on s-SWCNTs wrapped with bovine serum albumin (BSA). The fabricated biosensor was characterized and confirmed by Fourier-transform infrared spectroscopy (FTIR), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV). In the presence of MP, the effective interaction between AChE and MP favours the accumulation of MP-AChE complex on the glassy carbon electrode (GCE) surface which reduces the electron transfer property. Based on this interaction, detection of various concentration of MP was demonstrated by SWV using BSA/AChE-Glu-s-SWCNTs composite modified electrode. The proposed biosensor exhibited a wide linear range (WLR) for MP target in 100 mM phosphate buffered saline solution (PBS) (pH 7.4) from 1 x 10(-10) M to 5 x 10(-6) M with a limit of detection (LOD) of 3.75 x 10(-11) M. In addition, the BSA/AChE-Glu-s-SWCNTs/GCE biosensor showed good repeatability and reproducibility for MP detection. Moreover, the proposed biosensor showed better electrode stability when stored at 4 degrees C. This new electrochemical biosensor is also exhibited high selectivity and sensitivity for MP, which made it possible to test MP in real strawberry and apple juices. Furthermore, the BSA/AChE-Glu-s-SWCNTs/GCE offered a favourable electron transfer between the acetylthiocholine chloride (ATCI) and electrode interface than BSA/AChE-s-SWCNTs/GCE, s-SWCNTs/GCE and bare GCE. (C) 2019 Elsevier B.V. All rights reserved.

A non-noble metal-based bimetallic Cu–Ni system for the conversion of 4-nitrophenol and effective recyclability by magnetic retrieval of the catalyst.

We synthesized an MoS2/f-MWCNTs/ZnO composite and successfully used it to prepare an electrochemical sensor for the selective detection of AA in blood serum samples.

Two dimensional (2D) layered materials are receiving great attention due to various chemical functionality and anisotropic properties which are related to the crystalline arrangement of atoms. Their biocompatibility along with their structural, electrical and mechanical properties created interest in various fields of science and technology. The materials are flexible, transparent, light weight and have high stability. 2D layered materials are highly electrically and thermally conductive in nature. Additionally, phase boundaries and dynamic behavior can be observed in the same materials. It was expected that these layered 2D materials can be used as electrocatalyst to study their interactions with various molecules by electrochemical methods. The 2D materials based electrode have shown promising electro-catalytic activity, higher sensitivity, with selectivity, more stability and biocompatibility when used in chemical and biosensor applications. Interestingly, various kind of layered 2D materials can be easily synthesized without any sophisticated instruments. In this review, we have discussed about unique features of layered materials and various electrochemical exfoliation methods reported to prepare 2D layered materials (For example; hexagonal boron nitride (hBN), molybdenum disulfide (MoS2), molybdenum diselenide (MoSe2), tungsten dsulfide (WS2) and tungsten diselenide (WSe2)) with fewer defects at a relatively low cost. In addition, the use of 2D layered materials for electrochemical sensor fabrication and detection of pesticides were highlighted with their applications in real-world samples. Since, pesticides are highly toxic even at very low concentrations, it is very important to identify and detect their concentration level in fruits, vegetables and food to ensure human health and safety. For this purpose, 2D layered materials based electrochemical sensors have been demonstrated as a promising alternative method. The keep increasing demand for wearable/flexible sensor may utilize the simple electrochemical synthetic methods and electrode modification strategies to prepare electrochemical transducers for on-site pesticides detection in food samples with relatively low-cost. (C) 2018 The Electrochemical Society.

A rapid decrease in the availability of non-renewable fossil fuels has initiated the search for alternative fuels. Biodiesel obtained from various feedstocks has proved to be an effective alternative source for diesel engines due to its convincing fuel characteristics. The oxidation property of biodiesel is influenced by external factors such as sunlightand exposure to atmosphere.The oxidation stability of biodiesel can be improved by the addition of antioxidants which may be synthetic or natural. Natural antioxidants are more effective than synthetic ones in terms of economic value as well as prevention of adverse carcinogenic effects. Natural antioxidants, namely, ginger, Moringaoleifera, oregano, basil, and clove were extracted and used for the present study. The antioxidant activity of the additives was analyzed by DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical scavenging activity. The DPPH scavenging effect was calculated in terms of % by using absorbance values recorded with UV spectrophotometer. Among the antioxidants used, clove additive was found to be more efficient in enhancing the oxidation stability, with scavenging effect of 42.23%, 47.67%, 51.62%, and 55.61% for 500, 1000, 1500, and 2000ppm, respectively. It was also observed that the scavenging activity increased with the concentration of antioxidant additives, and the maximum value was recorded at a concentration of 2000ppm. Mahua oil methyl ester (MOME) was selected as biodiesel for the present study for which the oxidation stability has to be evaluated. The oxidation stability of MOME was measured in terms of induction period using theRancimat method which does not meet the required standards. The oxidation stability of MOME, MOME+ginger 2000, MOME +M.oleifera 2000, MOME +oregano 2000, MOME +basil 2000, and MOME +clove 2000 was evaluated. The highest induction period was observed to be 38.44h for MOME+clove 2000 blend. Hence, clove additive was found to be more effective among the selected natural antioxidants in terms of increasing the scavenging effect as well as increasing the oxidation stability of MOME. Thus, the addition of natural antioxidants can be recommended to improve the oxidation stability of biodiesel based on their scavenging effect which can be further validated by means of the Rancimat method in terms of the induction period

Herein, we demonstrated synthesis and application of silver nanoparticles (Ag-NPs) decorated nitrogen doped single-walled carbon nanotube through a one-step thermal-reduction method using melamine as the nitrogen source. Field-emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR) and X-ray diffraction data confirmed the successful synthesis of Ag-NPs functionalized nitrogen doped single-walled carbon nanotubes(Ag-N-SWCNTs). The nitrogen-doping notably modified the properties of the SWCNT and it showed stronger affinity for the attachment of Ag-NPs. By integrating the high surface area and electrical properties of N-SWCNTs with Ag-NPs, the obtained Ag-N-SWCNTs nanocomposite showed high catalytic activity than N-SWCNTs and pristine-SWCNTs. The enzyme-based methods have some disadvantages. For example, high fabrication cost and poor stability, due to these intrinsic disadvantages, non-enzymatic sensors have received more interest in fabrication of sensors. A non-enzymatic electrochemical urea sensor was developed by modifying glassy carbon electrode (GCE) with Ag-N-S WCNTs and a layer of Nafion (Nf). Thus, the fabricated sensor exhibited lower limit of detection (4.7 nM), with an enhanced sensitivity of 141 mu AmM-l cm(-2) for urea detection in the range of 66 nM to 20.6 mM(R-2 = 0.966). The reliability of the as-fabricated sensor was successfully investigated by using it to detect urea in tap water and milk samples. The NF/Ag-N-SWCNTs based urea sensor offers several advantages such as simple fabrication procedure, non-enzymatic and low-cost, so this sensor can be applied to detect urea in various samples from food, fertilizer industries and environmental fields. Moreover, the modified electrode showed phenomenal stability with no loss in activity of storage under ambient conditions. In addition, the novel hybrid NF/Ag-N-SWCNTs/GCE showed high selectivity toward urea with good repeatability and reproducibility further confirmed that this method can be utilized for detection of urea. (C) The Author(s) 2018. Published by ECS.

A simple electroanalytical method was developed to detect dopamine (DA) neurotransmitter by using carbon quantum dots (CQDs) modified electrode. To synthesis CQDs, a green electrochemical method was adopted and graphite rods were used as anode and cathodes in 0.1 M NaOH/ethanol (EtOH) as the electrolyte solution. As-synthesized CQD showed different particle sizes depending on the applied current with time as characterized by UV-visible spectroscopy. The particle size, lattice structure and functional groups of CQDs were analyzed by the HR-TEM, XRD and FT-IR, respectively. The CQD exhibited a green fluorescence under UV light (365 nm). Moreover, CQD dispersion was used to modify glassy carbon electrode (GCE) and screen-printed carbon electrode (SPCE) to study their electrochemical and electrocatalytic properties. The both GCE/CQD and SPCE/CQD showed higher electrocatalytic activity toward oxidation of dopamine (DA) in phosphate buffered saline (PBS) solution (pH = 7.4). In order to avoid interferences, Nafion (Nf) layer was coated on the CQD film modified electrode. The effect of scan rate on DA oxidation was studied from 10 to 150 mV/s. The calibration curve was recorded for DA from 1 to 7 mu M using a SPCE/CQD and the limit of detection was found to be 0.099 mu M. The observed electro-catalytic activity of the CQD was attributed to their negatively charged functional groups which attracted positively charged DA in 0.1 M PBS. In addition, detection of DA in spiked human urine sample was demonstrated with satisfactory recovery analysis. (C) The Author(s) 2018. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License.

In the present work, coral like hierarchical magnesium oxide (MgO) incorporated fly ash (FA) composite (FAMgO) synthesised by sol-gel method was evaluated for the adsorption of Reactive Black 5 (RB5) azo dye from aqueous solution. Adsorbent characterization using FE-SEM, XRD and FT-IR ascertained the formation of the FAMgO composite. Batch mode sorption studies were carried out for RB5 azo dye removal as a function of pH, FAMgO dose, initial dye concentration and temperature. The compliance of Langmuir isotherm model (R-2 = 0.999) corroborated the homogeneous nature of sorption of RB5 dye onto FAMgO with the sorption capacity (Q(max)) of 48.78 mg g(-1). The regression coefficient value revealed the best fit of pseudo-second-order model with the Q(e) value of 29 mg g(-1). The thermodynamic parameters such as Delta G degrees, Delta H degrees and Delta S degrees suggested the spontaneous and endothermic nature of RB5 dye sorption onto FAMgO and suitable mechanism has been proposed. (C) 2018 Elsevier B.V. All rights reserved.

Composite materials have the perk of combining a number of properties, which are not usually found together in a single material. The Hybrid Fiber composite solves the increasing need for Eco friendly materials coupled with high durability and strength. HFC has a wide range of applications in the field of aerospace, auto motives, civil constructions and electronics at a cost, which is lower than that of the traditional fibers like GFRP. Drilling is one of the primary operations adopted by industries for material working and component building. In this paper, the seminal process parameters - spindle speed, feed rate and the drill diameter are analysed and a Fuzzy model is burgeoned predicting the Thrust force and Torque for drilling Hybrid fiber Composite (HFC). The results indicate that the Fuzzy prediction model is effective and facilitates a better and easier artificial intelligence modelling.

AIMS:To study the toxicity of ABVE-PC (doxorubicin, bleomycin, vincristine, etoposide, prednisone and cyclophosphamide) and modified-BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone) in intermediate-risk and high-risk Hodgkin lymphoma patients.METHODS:High-risk patients received 4 cycles of modified-BEACOPP (m-BEACOPP) plus 4 cycles of ABVD. Intermediate-risk patients received 4 cycles of ABVE-PC plus 2 cycles of ABVD.RESULTS:From 2010 to 2014, 17 patients received 66 cycles of m-BEACOPP and 9 patients received 40 cycles of ABVE-PC. In the m-BEACOPP and ABVE-PC courses, respectively, significant thrombocytopenia (<50,000/mm(3)) occurred in 10.6% vs 0% of courses; anemia (Hb. <8 gm/dl) in 27.3% vs 15%; neutropenia (ANC<500/mm(3)) in 46.9% vs 32.5%; and febrile neutropenia in 33.3% vs. 22.5%. Only episode of documented infection (hepatic abscess) occurred in ABVE-PC. There were no episodes of sepsis, typhlitis or pneumonia in either group. All 26 patients are in remission with a median follow-up of 35 months (range, 17-61); and there have been no relapses. Two of 26 (7.7%) patients failed to achieve rapid early response after 2 cycles and complete remission after 4 cycles of chemotherapy; both achieved remission with more intensive regimens followed by radiation. The remaining 24 patients did not receive radiation therapy.CONCLUSIONS:Both m-BEACOPP and ABVE-PC regimens have acceptable toxicity; and thus can be used in most centres with optimum supportive care facilities. They offer promising response rate and relapse free survival without the need for radiation therapy in most patients; and thus may be considered for children with high-risk and intermediate-risk Hodgkin lymphoma.

OBJECTIVE:To define the efficacy and safety of low-dose rasburicase in children from south India with hematologic malignancies.METHODS:This study is a retrospective analysis of data on 41 children with hematologic malignacies with laboratory evidence of tumor lysis syndrome (TLS) or clinical features indicating high risk for developing TLS. Patients were treated with rasburicase in doses of 0.1-0.15 mg/kg dose, repeated when necessary.RESULTS:Male : Female ratio was 32:9. Thirty-six children had laboratory evidence of TLS and 5 were at risk for TLS. Diagnoses were T-cell acute lymphoblastic leukemia (ALL), 19; Pre-B ALL, 17; B-non-Hodgkin lymphoma (NHL), 2; T-NHL, 2; and acute myeloid leukemia (AML), 1. Initial plasma uric acid (PUA): median, 8.5 mg/dl (range, 4.3 to 45.5). Six had creatinine levels of >2 mg/dl on admission; and 10 had peak PO4 levels of >10 mg/dl. Dose of rasburicase used: median, 0.12 mg/kg (range, 0.08-0.24). Median reduction of PUA at 6 h: 80 % (range 40 to 98 %). Twenty-seven needed only one dose; 12 needed 2 or 3 doses; and two needed 5 doses each. One child required dialysis. None of the children developed anaphylaxis or hemolysis and there were no deaths from TLS.CONCLUSIONS:Low-dose rasburicase (0.1-0.15 mg/kg) is safe and effective in reducing PUA in Indian children with lymphoid malignancies, and thus it may reduce the risk of renal failure from TLS.

There has been a heavy interest in generalized processor sharing (GPS) based fair queuing algorithms modeled and implemented on wireline networks [1, 2]. The core reason for this is that most wired networks (ethernet, optical networks) have channels which are very rarely prone to errors. In other words, wireline channels most often are able to transmit what is intended with very less probability of error and channel malfeasance. Wireless channels on the other hand are very bursty in nature besides having higher chances of channel malfeasance compared to wireline channels. Most wireless fair scheduling adaptations work on the basis that flows that are error free occupies the complete bandwidth at any point of time and those that are faulty are allowed to reclaim later once channels recover [1, 2, 5]. In this paper we propose a wireless fair scheduling model where channels that reclaim, for compensation are controlled so that redundant data does not flow on the network for long.