Silicon nanoparticles as a fluorometric probe for sensitive detection of cyanide ion and its application in C. elegans bio-imaging.

In recent years, silicon nanoparticles (Si NPs) have been explored as a promising alternative to traditional organic fluorophores in optical sensing and bioimaging applications owing to their exceptional optical properties and negligible toxicity. In this study, water-dispersible Si NPs were prepared from a 3-aminopropyl trimethoxysilane precursor using a facile one-pot process. The as-prepared Si NPs exhibited excitation-wavelength-dependent fluorescence properties and bright green fluorescence at 530 nm upon excitation at 420 nm. The fluorescence properties of Si NPs remained unperturbed under various physiological conditions, such as varying pH, ionic strength, and incubation time. A sensitive fluorometric turn-off sensor for cyanide ion (CN-) detection was devised based on the unique fluorescence properties of Si NPs. The Si NPs-based detection assay showed a good linear response toward CN- ranging between 0 and 33 µM, with a limit of detection as low as 0.90 nM. Caenorhabditis elegans is used as a model organism to evaluate the in vivo toxicity and molecular imaging capability of Si NPs.

Electro-oxidation of heavy metals contaminated water using banana waste-derived activated carbon and Fe3O4 nanocomposites.

The main objective of this study was to banana waste-derived activated carbon (BWAC) make a high pore surface area was prepared and composited with Fe3O4 via a facile hydrothermal method. Various physiochemical characteristics of the prepared samples were evaluated using XRD, FTIR, FESEM, Raman Spectroscopy and XPS analysis. In addition, cyclic voltammetry and electrochemical impedance spectroscopy analyses were performed to determine the electrochemical properties of the prepared samples. The Fe3O4/BWAC sample showed a higher capacitance (285 F g-1) than BWAC at the same scan rate of 10 mV s-1. The capacitive deionization (CDI) cell configuration was varied, and its electro-sorption and defluoridization efficiencies were analyzed during the lead (Pb2+) removal 90%. An asymmetric combination of electrodes in the CDI cell exhibited better heavy metal removal performance, possibly due to the synergistic effect of the high surface area and the balance between the active adsorption site and the overlapping effect of the EDL. As a result, Fe3O4/BWAC could be a potential resource for supercapacitors and CDI electrodes, and the novel Fe3O4/BWAC nanocomposites outstanding performance suggests that they could be helpful for future energy storage and environmental applications.