Electrothermal atomization—the way toward absolute methods of atomic absorption analysis

A molecularly imprinted polymer (MIP) material was synthesized for use as an in-tube solid-phase microextraction (SPME) adsorbent. The inherent selectivity and chemical and physical robustness of the MIP material was demonstrated as an effective stationary-phase material for in-tube SPME. An automated and on-line MIP SPME extraction method was developed for propranolol determination in biological fluids. This simplified the sample preparation process and the chromatographic separation of several beta-blocker compounds. The method developed for propranolol showed improved selectivity in comparison to alternative in-tube stationary-phase materials, overcoming the limitations of existing SPME coating materials. Preconcentration of the sample by the MIP adsorbent increased the sensitivity, yielding a limit of detection of 0.32 microg/mL by UV detection. Excellent method reproducibility (RSD 500 injections) were observed over a fairly wide linear dynamic range (0.5-100 microg/mL) in serum samples. To our knowledge, this is the first report on the automated application of a MIP material for in-tube SPME. The method was inexpensive, simple to set up, and simplified the choice of SPME adsorbent for in-tube extraction. The approach can potentially be extended to other MIPs for the determination of a wide range of chemically significant analytes.

In-tube moleculary imprinted polymer solid-phase microextraction for the selective determination of propranolol.

A review is presented on the historical, fundamental, and practical aspects of microwave-induced plasmas (MIP) and their application to spectrochemical analysis. In particular, the mechanism of formation and stabilization of a microwave discharge is explored and possible excitation processes involving analyte atoms are described. Conditions under which a MIP can be operated are delineated and instrumentation necessary for MIP spectroscopy is described in detail. Methods for sample introduction into a MIP are reviewed and evaluated critically and the performance of MIP sources in real sample determinations is evaluated. Overall, the MIP appears to be a highly promising and under-utilized source in atomic spectrometry.

Microwave-Supported Discharges:

Mechanism and kinetics of thermal decomposition of carbonates

Ultratrace metals in some environmental and biological systems.

Vaporization and atomization of samples with a carbon filament atomizer

The determination of germanium by atomic absorption spectrometry with a graphite tube atomizer

A comparative study of the determination of zinc and molybdenum by atomic absorption spectrometry with a carbon filament atom reservoir

A number of workers have used molecular sieves to separate carbon monoxide from air (1,2,3) and it has been shown that PORAPAKA Ω is suitable for the resolution of carbon dioxide and sulphur dioxide from air (3,4,5). However, the sensitive detection of such gases frequently presents problems without recourse to the use of large sample volumes.

A Method for the Determination of Carbon Monoxide, Carbon Dioxide, Nitrous Oxide and Sulphur Dioxide in Air by Gas Chromatography Using an Emissive Helium Plasma Detector

A study is being made of the operating parameters and interferences in the atomic absorption determination of an element which is difficult to atomise (Mo) using a filament atom reservoir. A comparison is made with an element which is readily atomised (Zn). It is possible that this device is better suited in real situations to the determination of involatile elements such as Mo and in this instance especially using a hydrogen/nitrogen sheathing gas. There were numerous interferences in the case of Zn, but only tungsten produced a significant effect in the determination of Mo. The complete text of this paper has been published in Analytica Chimica Acta , 66 (1973) 171–178.

D.J. Johnson

Papers

Vaporization and atomization of samples with a carbon filament atomizer

The determination of germanium by atomic absorption spectrometry with a graphite tube atomizer

A comparative study of the determination of zinc and molybdenum by atomic absorption spectrometry with a carbon filament atom reservoir

A Method for the Determination of Carbon Monoxide, Carbon Dioxide, Nitrous Oxide and Sulphur Dioxide in Air by Gas Chromatography Using an Emissive Helium Plasma Detector

Study of the determination of molybdenum by atomic absorption spectrometry using a carbon filament atom reservoir