Melamine-derived N-rich C-entrapped Au nanoparticles for sensitive and selective monitoring of dopamine in blood samples.

Several neurological disorders, including Parkinson's disease, schizophrenia, human immunodeficiency virus infection, and restless leg syndrome, majorly result from disruption in the dopamine (DA) level. Thus, useful information about the treatment and prevention of various genetic majorly mental health problems can be obtained through precise and real-time monitoring of DA. Herein, we report the fabrication of novel N-rich carbon-coated Au nanoparticles (NC@Au-NPs) by deriving from melamine-crosslinked citrate-stabilized Au NPs. NC@Au-NPs offer fast electro-oxidation efficacy towards DA, because of strong electrostatic attraction between negatively charged NC@Au-NPs and positively charged DA. The catalytic efficacy and shelf life of the designed system were further boosted by applying a mixture of polydopamine (PDA) and benzimidazolium-1-acetate ionic liquid (IL) as a sandwich between the working electrode surface (graphitic pencil electrode: GPE) and the designed nanohybrid NC@Au-NPs as a redox mediator. The results indicate that the designed novel NC@Au/PDA-IL/GPE exhibits excellent sensitivity, selectivity, and reproducibility over a wide linear range (50-1000 nm) and a low detection limit of 0.002 µM ± 0.001 as well. The developed sensor was successfully applied to monitor DA in the blood of COVID-19 quarantined patients and pharmaceutical samples with high accuracy, thus suggesting a powerful tool for the diagnosis of mental problems.

CuO Hollow Cubic Caves Wrapped with Biogenic N-Rich Graphitic C for Simultaneous Monitoring of Uric Acid and Xanthine.

Herein, we synthesized hollow cubic caves of CuO (HC) and wrapped it with N-rich graphitic C (NC), derived from a novel biogenic mixture composed of dopamine (DA) and purine. The synthesized NC wrapped HC (NC@HC) sensor shows enhanced electrocatalytic efficacy compared to unwrapped CuO with shapes including HC, sponge (SP), cabbage (CB), and solid icy cubes (SC). The shape and composition of synthesized materials were confirmed through field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS), whereas interfacial surface energy was calculated through contact angle measurement. The designed NC@HC sensor shows a remarkable response toward the simultaneous detection of uric acid (UA) and xanthine (Xn) with detection limits of 0.017 ± 0.001 (S/N of 3) and 0.004 ± 0.001 µM (S/N of 3), respectively. In addition, this platform was successfully applied to monitor UA from the gout patient serum. To the best of our knowledge, this is the first report on using such novel NC@HC materials for the simultaneous monitoring of UA and Xn.

Design of Gravel-Sand Filter for Arsenic Removal: A Case Study of Muzaffargarh District in Pakistan.

Arsenic decontamination of drinking water has grabbed significant attention due to arsenic's serious effects on health. A novel gravel-sand filter (GSF) holding zero-valent iron plates was designed and constructed in Muzaffargarh district (Pakistan) for arsenic removal from drinking water with lower iron concentration (0.3 ppm). The GSF efficiently removed arsenic up to 99.99% with long-term stability. The GSF provides 800 liters of arsenic-free drinking water in 39 hours with a rate of 2.5 L/h. A tentative mechanism for arsenic removal is evaluated and described on the basis of oxidation-coagulation-adsorption processes. Chemical composition of underground water is also analyzed and discussed. This GSF design will open a new avenue for arsenic removal and can be extended to other parts of the world.

Glucomannan based polyurethanes: A critical short review of recent advances and future perspectives.

Polysaccharides derived from plants are one of the largest groups of natural compounds that offer potentially beneficial functions and properties. Glucomannan, a bioactive polymer belonged to mannan family of polysaccharides is fairly abundant in nature along with superior gelling and film forming properties. Glucomannan and its derivative with several synthetic polymers are used in a biomedical and food sector especially. Polyurethanes (PUs), a commercially useful class of polymers are extensively used in both industry and everyday life because they retain exceptional properties of both plastics and elastomers. This review addresses the properties and applications of glucomannan based materials with the aim to be explored this less attempted polymer further. Furthermore this paper also presents an overview of current status and perspectives of glucomannan based polyurethane materials.