Implementation of a conductivity cell electrode as an ion chromatography detector.

This technical note illustrates the possibility of using a conductivity cell electrode (CCE) as an ion chromatography (IC) detector to extend the application fields of this analytical technique. A conventional non-suppressed IC system consists of an eluent delivery pump, a separation column, column oven, and conductivity detector (CD). In this study, the conventional CD, which is one of the expensive parts of the instrument, is replaced with a relatively inexpensive CCE, leading to comparable peak resolution, detection sensitivity, and relative standard deviation. The separation effectiveness was retained and the developed IC-CCE system was successfully applied to the simultaneous separation of inorganic anions (SO42-, Cl-, and NO3-) and cations (Na+, NH4+, K+, Mg2+, and Ca2+) in three natural mineral water samples, with good accordance between the monitored values obtained using the CCE and CD. The commercially available CCE is potentially suitable for application as an IC detector for monitoring ionic components with overall IC cost reduction.

Simple mercury determination using an enclosed quartz cell with cold vapour-atomic absorption spectrometry.

A simple method for determining total inorganic mercury (Hg) in solution using an enclosed quartz cell applying cold vapour-atomic absorption spectrometry (CV-AAS) can reduce sample volume, reductant, and cost compared with those of official methods. The Hg determination under the optimised conditions achieves precision similar to that of conventional CV-AAS.

Determination of dieldrin in wool products by gas chromatography with microwave-assisted extraction.

Dieldrin is a moth-proofing agent that was banned by the Stockholm Convention in 2001. The amount of dieldrin in wool products was measured by a microwave-assisted extraction (MAE) method. The optimal conditions were as follows: extraction solvent, acetone/n-hexane (1:1 v/v); extraction temperature, 110 degrees C; extraction time, 10 min; solvent volume, 25 mL. When six samples were used, dieldrin contents determined by GC with the proposed MAE agreed closely with those by the Japanese official method using GC with solvent extraction and cleanup by column chromatography. The proposed MAE has two merits. First, the pretreatment of the MAE needs only 4 h for 11 samples, while that using the Japanese official method needs 2 days for six samples. Second, the volume of organic solvents used for the proposed method was only about one-tenth of that used in the Japanese official method. Our proposed method seems to be easy and useful for daily (routine) tests. Dieldrin contents of 28 used wool products, which were obtained from local clothing shops and ordinary homes, were determined by GC with the proposed MAE, and six products contained dieldrin (0.310-175 ppm). The dry cleaning of the woolen yarn containing 175 ppm dieldrin did not remove a significant amount of dieldrin. Therefore, it seems likely that dieldrin is still distributed slightly but widely throughout the world.