Quantitative determination of zinc in milkvetch by anodic stripping voltammetry with bismuth film electrodes.

Bismuth film electrode (BiFE) was shown to be an attractive alternative to common mercury film electrode (MFE) for anodic stripping voltammetric measurements. In this study, bismuth film, that was in situ deposited onto glassy carbon electrode, was used to detect zinc content of milkvetch, used in traditional Chinese medicine. Variables affecting the response have been evaluated and optimized.

Solid-phase spectrophotometric determination of nickel in water and vegetable samples at sub-mug l(-1) level with o-carboxylphenyldiazoaminoazobenzene loaded XAD-4.

A highly sensitive and selective solid-phase spectrophotometric method for the determination of sub-mugl(-1) level nickel(II) is described. Nickel(II) was sorbed on a styrene-divinylbenzene-type resin Amberlite XAD-4 as a Ni(II)-o-carboxylphenyldiazoaminoazobenzene (o-CDAA) complex. At pH 9.

Preconcentration and determination of trace elements with 2-aminoacetylthiophenol functionalized Amberlite XAD-2 by inductively coupled plasma-atomic emission spectrometry.

2-Aminoacetylthiophenol (AATP)-modified Amberlite XAD-2 has been synthesized by coupling it through NNNH group. The resulting chelating resin, characterized by elemental analysis, thermogravimetric analysis (TGA) and infrared (IR) spectra, was used to preconcentrate Cd, Hg, Ag, Ni, Co, Cu and Zn ions. Several parameters, such as distribution coefficient and sorption capacity of the chelating resin, pH and flow rates of uptake and striping, volume of sample and eluent, were evaluated.

Spectrophotometric determination of lead in vegetables with dibromo-p-methyl-carboxysulfonazo.

A new highly sensitive and selective chromogenic reagent dibromo-p-methyl-carboxysulfonazo (DBMCSA) was synthesized and studied for the spectrophotometric determination of lead in detail. In 0.25 M phosphoric acid medium, which greatly increases the selectivity, lead reacts with DBMCSA to form a 1:2 blue complex, having a sensitive absorption peak at 648 nm.

Spectrophotometric determination of lead in foods with dibromo-p-methyl-bromosulfonazo.

The synthesis and purification of a new chromogenic reagent dibromo-p-methyl-bromosulfonazo (DBMBSA) are described. A method is proposed for the spectrophotometric determination of lead with DBMBSA. In 0.

Biosorption and preconcentration of lead and cadmium on waste Chinese herb Pang Da Hai.

The biosorption behavior of the solid waste Chinese herb Pang Da Hai (seeds of Sterculia lychnophera Hance) was studied as a sorbent for trace lead and cadmium. The solid waste Chinese herb Pang Da Hai has good sorption and desorption properties for Pb and Cd. The sorbed waste Chinese herb Pang Da Hai was both easily eluted with 0.