•Simple synthesis of SnO2 nanoparticles.•Utilization of SnO2 nanoparticles for modification of sensor.•Electrochemical characterization through CV and EIS studies.•Quantification of vitamin C and ...vitamin B6 in real samples.
Vitamins are considered as the essential nutrients because they perform vital role for normal metabolism and healthy growth. Our body cannot synthesize vitamins, therefore, they must be taken through a balanced diet because their deficiency can cause several diseases. A number of pharmaceutical formulations are available containing a range of vitamins. It is important to determine vitamin content from them through easy and efficient method. This study reports the simultaneous determination of two important water-soluble vitamins (vitamin C and B6) from multivitamin tablets with high accuracy and high sensitivity. The work is conducted in two phases; first includes the synthesis of tin oxide (SnO2) nanoparticles via aqueous chemical growth method and their characterization through Transmission electron microscopy (TEM), Energy-Dispersive X-ray (EDX), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). While second part include simultaneous electrochemical determination of vitamin C and B6 from multivitamin tablets. The cyclic voltammetry was used for the development of new method using SnO2/GCE modified electrode. In CV, two well resolved peaks obtained under optimized conditions which confirm that both vitamins can be determined at the same time. The modified electrode based on SnO2 nanoparticles was successfully applied for the determination of vitamin C and vitamin B6 in pharmaceutical samples with the limit of detection of 0.067 µM for VC, 0.048 µM for B6 respectively.
An innovative electrochemical sensing method is introduced for dihydroxy benzene (DHB) isomers, specifically hydroquinone (HQ) and pyrocatechol (PCC), employing a ...zinc-oxide/manganese-oxide/reduced-graphene-oxide (ZnO/MnO
2
/rGO) nanocomposite (NC) as an electrode modifier material. Comprehensive characterization confirmed well-dispersed ZnO/MnO
2
nanoparticles on rGO sheets. Electrochemical analysis revealed the ZnO/MnO
2
/rGO-NC-based modified electrode possesses low electrical resistance (126.2 Ω), high electrocatalytic activity, and rapid electron transport, attributed to the synergies between ZnO, MnO
2
and rGO. The modified electrode demonstrated exceptional electrochemical performance in terms of selectivity for the simultaneous detection of HQ and PCC. Differential pulse voltammetry studies validated the proposed sensor’s ability to detect HQ and PCC within linear response ranges of 0.01–115 μM and 0.03–60.53 μM, with detection limits of 0.0055 µM and 0.0053 µM, respectively. Practical validation using diverse water samples showcased excellent percent recovery of HQ and PCC using the ZnO/MnO
2
/rGO-based electrochemical sensor, underscoring the sensor’s potential for real-world applications in environmental monitoring.
Graphical abstract
The tandem extrusion method is quite famous for polymer foaming production in up-scale. In this method, two extruders coupled together for different functionality. The primary extruder used for ...melting, homogenizing the foaming agent in the melt. The secondary extruder used for reducing the melt temperature to the required foaming temperature limit. In this study, propose newly developed core-hole heat exchanger by replacing secondary extruder as an alternative solution. The heat transfer performance of the core-hole structure investigated in this work. According to heat transfer performance mainly focus on heat transfer rate, temperature distribution, local heat transfer coefficient, Nusselt number, and overall heat transfer coefficient in this work. The experiments were carried out on 180 °C, 190 °C, and 200 °C inlet temperature, whereas the flow rate was 08 to 20 kg/h with 4 unit of the interval. Non-homogeneous temperature distribution resulted in 08 kg/h and 180 °C of the inlet temperature, but overall average temperature approximately similar to surface temperature. Good mix ability and the uniform temperature achieved on 12 and 16 kg/h in all range of temperatures in this study. Whereas, 20 kg/h of mass flow rate reduces the temperature distribution quality of the melt. Because of the higher temperature difference and flow rate, higher heat transfer rate achieved on 200 °C and 20 kg/h. Convective heat transfer coefficient has been increased concerning flow rate and local point temperature difference. In this work, it investigated that 190 °C of inlet temperature gives a higher overall heat transfer coefficient on 16 and 20 kg/h of mass flow rate.
•A new application of Core-hole heat exchanger for polymer foaming production line.•The homogenous melt temperature distribution achieved using core-hole heat exchanger.•The HTC of polymer melt has investigated using core-hole heat exchanger.•The Nusselt Correlation has been developed for polypropylene melt flow.
The global average potato (Solanum tuberosum L.) production is 17.4 t ha.sup.-1. Even using the same potato varieties, there is a large gap between higher yields and lower yields among countries. ...Potatoes are a cash crop and a significant part of the global diet. Therefore, low soil fertility, soil-borne diseases, poor water quality, and pests seriously affect potato production in developing countries. To improve potato quality and production, it is necessary for the modern world to improve its potato cultivation techniques. Aeroponics cultivation is an alternative technology of soilless culture for effectively adapting to areas of the world where soil and water are in critical condition. In aeroponic systems, plant roots are suspended in the open air under controlled circumstances to replace the soil with artificially provided foam or plastic stents. Moreover, the nutrient solution is spread through atomization nozzles. This review provides insights into the potential use of aeroponics in complementing potato production in developing countries. Moreover, in most developing countries, this technology should be adopted after deliberate consideration to increase potato production. Key words: Aeroponics, nutrient solution, potato production, soilless culture, ultrasonic atomization.
Large amount of wastes are burnt or left to decompose on site or at landfills where they cause air pollution and nutrient leaching to groundwater. Waste management strategies that return these food ...wastes to agricultural soils recover the carbon and nutrients that would otherwise have been lost, enrich soils and improve crop productivity. The incorporation of liming materials can neutralize the protons released, hence reducing soil acidity and its adverse impacts to the soil environment, food security, and human health. Biochar derived from organic residues is becoming a source of carbon input to soil and provides multifunctional values. Biochar can be alkaline in nature, with the level of alkalinity dependent upon the feedstock and processing conditions. This study conducted a characterization of biochar derived from the pyrolysis process of eggplant and Acacia nilotica bark at temperatures of 300 °C and 600 °C. An analysis was conducted on the biochar kinds to determine their pH, phosphorus (P), as well as other elemental composition. The proximate analysis was conducted by the ASTM standard 1762-84, while the surface morphological features were measured using a scanning electron microscope. The biochar derived from Acacia nilotica bark exhibited a greater yield and higher level of fixed carbon while possessing a lower content of ash and volatile components compared to biochar derived from eggplant. The eggplant biochar exhibits a higher liming ability at 600 °C compared to the acacia nilotica bark-derived biochar. The calcium carbonate equivalent, pH, potassium (K), and phosphorus (P) levels in eggplant biochars increased as the pyrolysis temperature increased. The results suggest that biochar derived from eggplant could be a beneficial resource for storing carbon in the soil, as well as for addressing soil acidity and enhancing nutrients availability, particularly potassium and phosphorus in acidic soils.
Urea is one of the most important and widely exploited nitrogenous organic compounds in the agriculture and its availability can also be exercised in the human body. Urea is an important entity that ...plays certain crucial roles in human body e.g., it works as carrier of waste nitrogen and has major contribution in countercurrent exchange system. Moreover, high concentration of urea can lead toward several health concerns such as kidney failure, urinary tract obstruction, dehydration, renal failure, cachexia, nephritic syndrome, gastrointestinal bleeding, hepatic failure, and shock burns. To quantify the urea concentration in human body through urine, a new and highly sensitive electrochemical sensor based on β-SnWO
4
/rGO/GCE has been engineered. The electrocatalytic characteristics of proposed sensor were evaluated by exploiting different modes of voltammetry e.g., electrochemical impedance spectroscopy (EIS) and Tafel plot and cyclic voltammetry (CV). For effective and sensitive determination of urea, different parameters were optimized as scan rate 110 mV/s, BRB electrolyte pH 2, and potential window from − 0.5 to 0.7 V. The LOD and LOQ of the developed sensor for urea were observed as 0.00016 and 0.0005 µM, respectively. The real application of engineered sensor was tested in human urine samples. The recovery values of urine samples were found in acceptable range which prove the sensitivity and reliability of β-SnWO
4
/rGO/GCE.
Quercetin (Qu) is a most active biological flavonoid and it has a very wide spectrum of potential applications. Herein, we have synthesized ionic liquid assisted Co
3
O
4
nanostructures through an ...aqueous chemical growth method and fabricated a Co
3
O
4
modified GCE as an electrochemical sensor for the sensitive detection and determination of Qu. The proposed electrochemical sensor was not only prepared with a very easy, simple and cheap method but it was also found to be very selective, sensitive and highly stable for the detection of Qu in standard solutions as well as in real food samples like onion, honey and green tea. The prepared electrochemical sensor has shown an excellent electrochemical response for Qu with a wide range of detection from 0.01 to 3 µM. The oxidation current response of Qu on Co
3
O
4
modified GCE was found 4 times higher than the response of bare GCE which is due to the high conductivity, tremendous catalytic ability and large surface area of Co
3
O
4
nanostructures. The limit of detection (LOD) and the limit of quantification (LOQ) for Co
3
O
4
/GCE sensor was calculated and found to be 0.0002 µM and 0.0007 µM respectively. While, the amount of Qu in real samples was found to be 5.367 µg/mL in honey, 15.58 µg/g in onion and 3.473 mg/g in green tea respectively. In comparison to the previously reported sensors, the prepared Co
3
O
4
/GCE sensor has shown a higher electrocatalytic capability, remarkable stability, super sensitivity and adequate selectivity for the determination of Qu in standard solutions as well as in real samples.
Atrazine-imprinted reduced graphene oxide composite with its enhanced functionalities and porous surface was successfully synthesized and applied for the selective determination of atrazine in ...complex matrices. Scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction studies revealed the imprinted polypyrrole beads formation on the reduced graphene oxide lining. Resultant composite was used to modify screen-printed electrode which then showed improved properties for voltammetric determination of atrazine. Measurements were carried out via square wave voltammetry giving a peak at − 0.9 V corresponding to the reduction of atrazine heterocyclic moiety. Obtained LOD and LOQ for atrazine were found to be 0.4 nmol/dm
3
and 1.2 nmol/dm
3
, respectively, at optimized parameters. The method was applied for the atrazine determination in complex aqueous matrices.
Graphic abstract
We report here the results of studies related to the fabrication of an electrochemical immunosensor for the detection of
Escherichia coli
ATCC 25922 using AuNPs-GCE-avidin-Ab-
E. coli
based on ...complex compound. In the presence of targeted bacteria, the specific antibody was coated on the surface with gold nanoparticles (AuNPs). The detailed morphology of synthesized AuNPs was confirmed using analytical techniques. The proposed immunosensor revealed a high electrocatalytic activity and linear response at the peak potential value over a wide concentration of
E. coli
ATCC 25922 from 10
1
to 10
5
CFU/mL. The results were correlated with the linear equation of (
R
2
= 0.991). The recorded results were responded in the presence of targeted
E. coli
ATCC 25922 with other bacterial strains such as
Salmonella typhi, Klebsiella aerogenes
, and
E. coli
O57:H7 indicating a high selectivity of electrochemical immunosensor. A combined artificial neural network (ANN) approach serves as a powerful model to understand and analyze the intelligent data of the digital transformation output. The determined regression method of the fabricated sensor was selected for evaluation of the ANN-based technique that initiated to be a superior known method. The applied technique confirmed a great practical approach to targeted bacteria in spiked samples of the sandwich complex. Therefore, the satisfactory result demonstrates the feature of simulation data attainment and analysis is highly reliable and attractive. Moreover, the constructed immunosensor may be used to screen contaminated water and prevents an epidemic of life-threatening infectious disease.
Pesticides are the most toxic substances that badly affect the quality of edible food products and the environmental sustainability. Bentazone has been globally considered as one of the most lethal ...pesticides claiming human life. For the determination of this pesticide, certain analytical procedures have been widely exploited, including electrochemical methods. The synthesis of NiO nanoseeds was carried out via aqueous chemical growth method using sodium dodecyl sulfate (SDS) as stabilizer that greatly enhanced the sensitivity and selectivity of the working electrode. The fabricated NiO nanostructures were directed for different characterization tools e.g., XRD, FE-SEM, and EDS that revealed phase purity, nanoseed morphology, and elemental composition of NiO. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to examine the conductive nature and electrocatalytic behavior of NiO. Different parameters, such as scan rate of 70 mV/s and phosphate buffer (PB) electrolyte (pH 7), were optimized for the sensitive determination of bentazone. At optimized conditions, the modified electrode manifested phenomenal Ipa response under linear dynamic range from 0.1 to 60 µM with lower limit of detection (LOD) (1.2 nM). The analytical applicability of modified sensor was tested in vegetable samples with satisfactory recoveries. We believe that this novel method will be highly useful for the practicable and sensitive determination of hazardous pesticides.
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