Poly-Phthalocyanine-Doped Graphene Oxide Nanosheet Conjugates for Electrocatalytic Oxidation of Drug Residues.

Donor and acceptor phthalocyanine molecules were copolymerized and linked to graphene oxide nanosheets through amidation to yield electrocatalytic platforms on glassy carbon electrodes. The platforms were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, UV/Vis spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The fabricated electrochemical catalytic surfaces were then evaluated toward electrocatalytic detection of ascorbic acid and tryptophan.

Removal of nickel(II) from aqueous solution by Vigna unguiculata (cowpea) pods biomass.

The potential to remove nickel(II) ions from aqueous solution using a biosorbent prepared from Vigna unguiculata pods (VUPs) was investigated in batch experiments. The batch mode experiments were conducted utilising the independent variables of pH (2 to 8), contact time (5 to 120 min), dosage concentration (0.2 to 1.

Human health risks due to heavy metals through consumption of wild mushrooms from Macheke forest, Rail Block forest and Muganyi communal lands in Zimbabwe.

The levels and sources of toxic heavy metals in Amanita loosii (AL) and Cantharellus floridulus (CF) mushrooms and their substrates were studied in some parts of Zimbabwe, Rail Block forest (mining town), Macheke forest (commercial farming), and Muganyi communal lands. The mushrooms and their associated soils were acid digested prior to Al, Pb, and Zn determination by inductively coupled plasma optical emission spectroscopy. The transfer factors, mushrooms-soil metal correlation coefficients, daily intake rates, weekly intake rates, and target hazard quotients were calculated for each metal.

Application of Opuntia ficus-indica in bioremediation of wastewaters. A critical review.

Heavy metal ion, pesticide and dye wastewaters cause severe ecological contamination with conventional treatment methods proving inadequate, unsuccessful or expensive to apply. Several biomaterials have recently been explored for the biosorption and biocoagulation-flocculation of pollutants from wastewaters. In the past 10 years, there has been an extensive research output on the use of biological materials such as agricultural wastes, chitosan, Moringa Oleifera, Eichhornia crassipes, bacteria, algae, Cactus plants etc.

Maize tassel-modified carbon paste electrode for voltammetric determination of Cu(II).

The preparation and application of a practical electrochemical sensor for environmental monitoring and assessment of heavy metal ions in samples is a subject of considerable interest. In this paper, a carbon paste electrode modified with maize tassel for the determination of Cu(II) has been proposed. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to study morphology and identify the functional groups on the modified electrode, respectively.

An amperometric biosensor based on horseradish peroxidase immobilized onto maize tassel-multi-walled carbon nanotubes modified glassy carbon electrode for determination of heavy metal ions in aqueous solution.

A biosensor for trace metal ions based on horseradish peroxidase (HRP) immobilized on maize tassel-multiwalled carbon nanotube (MT-MWCNT) through electrostatic interactions is described herein. The biosensor was characterized using Fourier transform infrared (FTIR), UV-vis spectrometry, voltammetric and amperometric methods. The FTIR and UV-vis results inferred that HRP was not denatured during its immobilization on MT-MWCNT composite.

Recent advances in polymeric materials used as electron mediators and immobilizing matrices in developing enzyme electrodes.

Different classes of polymeric materials such as nanomaterials, sol-gel materials, conducting polymers, functional polymers and biomaterials have been used in the design of sensors and biosensors. Various methods have been used, for example from direct adsorption, covalent bonding, crossing-linking with glutaraldehyde on composites to mixing the enzymes or use of functionalized beads for the design of sensors and biosensors using these polymeric materials in recent years. It is widely acknowledged that analytical sensing at electrodes modified with polymeric materials results in low detection limits, high sensitivities, lower applied potential, good stability, efficient electron transfer and easier immobilization of enzymes on electrodes such that sensing and biosensing of environmental pollutants is made easier.