Enhancement of molybdenum inductively coupled plasma emission by forming volatile species in organic solvents
1985; Royal Society of Chemistry; Volume: 110; Issue: 5 Linguagem: Inglês
10.1039/an9851000563
ISSN1364-5528
AutoresAlfredo Sanz‐Medel, José Enrique Sánchez Uría, Siro Arribas Jimeno,
Tópico(s)Analytical Chemistry and Sensors
ResumoThe formation of a volatile chemical form of a given analyte in water may lead to significant analytical enhancement of ICP emission. It is apparent, therefore, that extraction of a selected volatile compound of an element followed by its direct ICP detection in the organic extract would offer an easy means of enhancing the sensitivity of ICP-AES determinations (enhancement of pre-concentration ability and volatility effect).The possibility of enhancing ICP signals through a volatility effect in a given organic solvent was investigated by measuring relative intensities in the ICP for nine different chemical forms of molybdenum dissolved in butan-1-ol. Although the different compounds tested exhibit different volatilities, only Mo(CO)6 produced analytically advantageous ICP emission enhancements (by a factor of 3–4 at 202.03 nm and by a factor of 2.5–3 at the 313.26 nm Mo atomic line). The enhancement observed was virtually independent of the plasma conditions. Indirect aerosol transport efficiency measurements clearly demonstrated the transport (volatility) nature of the enhancement.Several organic solvents (butan-1-ol, xylene, chloroform and dichloromethane) were investigated as solvents for volatile and less volatile Mo compounds. The influence of the nature of the solvent on the Mo ICP signal and on the Mo(CO)6 enhancement is discussed. A comparative study of the performance of these solvents in the ICP showed that butan-1-ol is clearly superior for the determination of Mo (highest plasma stability, lowest memory effects, highest net signal, best detection limits and best precision).
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