Post column digestion methods for liquid chromatography-graphite furnace atomic absorption speciation of organolead and organotin compounds

Abstract

The chemical digestion of organometallics containing lead and tin is induced in the graphite cuvette of an atomic absorption spectrometer. The metal-containing components are digested and analyzed after the molecular species are separated by reversed phase liquid chromatography. The five lead species, tetramethyl-, trimethylethyl-, dimethyldiethyl-, methyltriethyl-, and tetraethyllead, are analyzed by using the peak storage sampling method and are digested with methanolic iodine. The organotin compounds analyzed include tetrapropyl-, tetrabutyl-, tetraphenyl-, and dibutyldichlorotin. These tin compounds are decomposed in the graphite furnace by the zirconium-treated surface of the cuvette. The application of these procedures to reduce species-dependent sensitivity in atomic absorption analysis of liquid chromatographic eluents is discussed.

Atomic emission spectrometric analysis of organic solutions by electrothermal carbon cup vaporization into an inductively coupled plasma

“…Therefore, it was necessary to reduce their volatilities so that no lead loss would occur. Iodine was chosen to do so by chemical stabilization (19,20). This iodine was added directly to the carbon cup.…”

“…There is no limitation with the solvents investigated and, therefore, solvent extractions and HPLC methods may be developed more fully. The coupling of the HPLC with this system would be similar to that utilized with graphite furnace atomic absorption spectrometry (20,21).…”

Lead speciation in rainwater samples by modified fused silica capillaries coupled to a direct injection nebulizer (DIN) for sample introduction in ICP-MS

“…Liquid chromatography has not been so widely used for the determination of organolead species. Again several types of detectors have been employed, the most commonly used have been AAS, [8][9][10] and ICP-AES, 11 but the sensitivity of both approaches is disappointing. Few approaches are capable of determining inorganic lead, ionic alkyllead and tetraalkyllead compounds with a single analytical method.…”

Element‐specific detectors for highpressure liquid chromatography (HPLC): acomputerized, automated HPLC‐graphitefurnace atomic absorption system

“…These substances occur at mg/1 or txg/1 concentrations in complex matrices which will obscure chromatographic peaks of interest or make their identification difficult. To overcome these difficulties graphite furnace atomic absorption spectrometers [3][4][5][6][7][8][9][10] and plasma emission spectrometers [11 and 12] have been used as element-specific detectors for high pressure liquid chromatography in manual [4] and automated modes [3, 5, 8 and 12]. This paper describes the construction and use of a computerized, automated interface between a high pressure liquid chromatograph (HPLC) and an Instrumentation Laboratory Model IL-555/151 graphite furnace atomic absorption spectrometer (GFAAS).…”