Determination of ultratrace levels of lead (II) in water samples using a modified carbon paste electrode based on a new podand

Cellulose-hydroxyapatite carbon electrode composite for trace plumbum ions detection in aqueous and palm oil mill effluent: Interference, optimization and validation studies

Environmental monitoring is important to determine the extent of eco-system pollution and degradation so that effective remedial strategies can be formulated. In this study, an environmentally friendly and cost-effective sensor made up of novel carbon electrode modified with cellulose and hydroxyapatite was developed for the detection of trace lead ions in aqueous system and palm oil mill effluent. Zinc, cadmium, and copper with lead were simultaneously detected using this method. The electrode exhibited high tolerance towards twelve common metal ions and three model surface active substances - sodium dodecyl sulfate, Triton X-100, and cetyltrimethylammonium bromide. Under optimum conditions, the sensor detected lead ions in palm oil mill effluent in the concentration range of 10-50 μg/L with 0.11 ± 0.37 μg/L limit of detection and 0.37 ± 0.37 μg/L limit of quantification. The validation using tap water, blood serum and palm oil mill effluent samples and compared with Atomic Absorption Spectroscopy, suggested excellent sensitivity of the sensor to detect lead ions in simple and complex matrices. The cellulose produced based on "green" techniques from agro-lignocellulosic wastes, in combination with hydroxyapatite, were proven effective as components in the carbon electrode composite. It has great potential in both clinical and environmental use.

Stripping voltammetric detection of copper ions using carbon paste electrode modified with aza-crown ether capped gold nanoparticles and reduced graphene oxide

A novel electrochemical sensor based on reduced graphene oxide (RGO) and kryptofix 21-capped gold nanoparticles (GNPs) has been proposed.

BINOL Macrocycle Derivatives: Synthesis of New Dinaphthyl Sulfide Aza Oxa Thia Crowns (Lariats)

In this research work, dinaphthyl sulfide diester was prepared from the reaction of 1,1′-thiobis (2-hydroxy naphthalene) and methylchloroacetate. Its aza-macrocyclic derivative was synthesized from the reaction of dinaphthyl sulfide diester and diethylenetriamine. Lariats were prepared from the reaction of chloroamides (four derivatives) and initial macrocycle. Chloroamides were synthesized from the reaction of amines (aniline, benzylamine, 8-amino quinoline and 4-amino azobenzene) and chloroacetyl chloride. All the materials were identified by IR,1H NMR,13C NMR, and mass spectroscopies, and elemental analysis.