Development of gas-phase sample-introduction techniques for analytical atomic spectrometry.

For the last 30 years, several types of gas-phase sample-introduction methods in analytical atomic spectrometry, i.e., atomic absorption spectrometry (AAS), atomic emission spectrometry (AES) and atomic fluorescence spectrometry (AFS), have been investigated and developed in the author's laboratory.

Determination of carbamate pesticide residues in vegetables and fruits by liquid chromatography-atmospheric pressure photoionization-mass spectrometry and atmospheric pressure chemical ionization-mass spectrometry.

A liquid chromatography-atmospheric pressure photoionization (APPI)-mass spectrometry method was developed for the determination of 22 carbamates including their metabolites in vegetables and fruits. For the optimization of APPI, several APPI ion source parameters were examined. As a result, many carbamates with APPI using the optimized parameter gave simple mass spectra, and a strong signal corresponding to [M + H](+) was observed except for aldicarb.

Simultaneous determination of bismuth and tellurium in steels by high power nitrogen microwave induced plasma atomic emission spectrometry coupled with the hydride generation technique.

An annular-shaped, high power nitrogen microwave induced plasma (N(2)-MIP) produced at atmospheric pressure by an Okamoto cavity, as a new excitation source for atomic emission spectrometry (AES), has been used for the simultaneous determination of bismuth and tellurium in steels with the hydride generation method. Under the optimized experimental conditions, the best attainable detection limits at the Bi I 195.389 nm and Te I 200.

Quantitative analysis of trace bulk oxygen in silicon wafers using an inert gas fusion method.

This paper describes a method for removing oxide film from the surface of silicon wafers using an inert gas fusion impulse furnace and precise determination of bulk oxygen within the wafer. A silicon wafer was cut to about 0.35 g (6 x 13 x 2 mm) and dropped into a graphite crucible.

Determination of chloramphenicol residues in fish meats by liquid chromatography-atmospheric pressure photoionization mass spectrometry.

A liquid chromatography-atmospheric pressure photoionization (APPI) mass spectrometry method was developed for the determination of chloramphenicol (CAP) in fish meats (young yellowtail and flatfish). For the optimization of APPI, several APPI ion source parameters and mobile phases were investigated. CAP with APPI using the optimized parameters gave simple mass spectra and a strong signal corresponding to [M-H]- was observed.

Liquid chromatography/mass spectrometric determination of patulin in apple juice using atmospheric pressure photoionization.

This paper describes a comparison between atmospheric pressure chemical ionization (APCI) and the recently introduced atmospheric pressure photoionization (APPI) technique for the liquid chromatography/mass spectrometric (LC/MS) determination of patulin in clear apple juice. A column switching technique for on-line extraction of clear apple juice was developed. The parameters investigated for the optimization of APPI were the ion source parameters fragmentor voltage, capillary voltage, and vaporizer temperature, and also mobile phase composition and flow rate.

Determination of carbon in aqueous solutions by atmospheric-pressure helium microwave induced plasma atomic emission spectrometry with gas-phase sample introduction technique.

A trace amount of carbon was determined by atmospheric-pressure helium microwave induced plasma atomic emission spectrometry (He-MIP-AES) with gas-phase sample introduction technique. This method was applied for the generation of a continuous flow of carbon dioxide by the acidification of carbonate ion and hydrogen carbonate ion for the determination of carbon. The generated carbon dioxide was separated from the solution by a simple gas-liquid separator, dried with a desiccant and swept into the MIP with helium carrier gas for analysis.

Determination of perfluorooctane sulfonate in river water by liquid chromatography/atmospheric pressure photoionization mass spectrometry by automated on-line extraction using turbulent flow chromatography.

A simple, fast and sensitive liquid chromatography/atmospheric pressure photoionization mass spectrometry (LC/APPI-MS) method, with automated on-line extraction using turbulent flow chromatography (TFC), was developed for the determination of perfluorooctane sulfonate (PFOS) in river water. In this method, following an on-line extraction by injection onto a column under TFC conditions, PFOS is back-flushed onto a reversed-phase column via on-line column switching, and resolved chromatographically at a laminar flow rate of 1 mL min(-1). Using this tandem LC-LC/APPI-MS system the extraction, separation and selective detection of PFOS in river water could be achieved with satisfactory selectivity and sensitivity.

Quantitative liquid chromatography-mass spectrometry determination of catechins in human plasma by automated on-line extraction using turbulent flow chromatography.

A simple, fast and sensitive liquid chromatography-mass spectrometry (LC-MS) method with automated on-line extraction using turbulent flow chromatography (TFC) for the determination of five catechins in human plasma was developed. In this method, after on-line extraction by its injection onto an extractor column at turbulent flow, five catechins were backwashed onto a reversed phase column via on-line column switching and separated chromatographically at a laminar flow of 1 ml min(-1). Using this tandem LC-LC-MS system, the extraction, the separation and the quantitation of five catechins in human plasma could be achieved with satisfactory selectivity and sensitivity.