Analytical performance evaluation of a 40.68 MHz inductively coupled plasma mass spectrometer

Effect of the plasma operating frequency on the figures of merit of an inductively coupled plasma time-of-flight mass spectrometer

“…In earlier work, contradictory trends were reported, and it was suggested by the authors that their results were an artifact of the secondary rather than of operating frequency. [8][9][10] Here, the ratios of oxide and doubly charged species were measured in the absence of a secondary discharge, and hence demonstrate unambiguously that operating frequency does not affect the formation of oxides or doubly charged species in a hot plasma. This trend also holds true for cold plasma conditions, where the presence of oxide species is greatly amplified.…”

“…1,2 Optimal nebulizer flow rates for 40 MHz systems are typically lower than those at 27 MHz, and the axial distributions of analyte and background ions are shifted to lower sampling depths in 27 MHz plasmas. 8,9 These results are not surprising, considering differences in the fundamental parameters for 27 and 40 MHz ICPs. 6 In contrast to ICP-AES, higher sensitivities and better detection limits are obtained in ICP-MS at 27 MHz.…”

“…Some researchers observed higher ratios of MO 1 /M 1 and M 21 /M 1 at one generator frequency, while others reported the opposite trend. [8][9][10] The presence of an intense secondary discharge might have complicated this comparison, as this type of discharge can alter the abundance of oxide and doubly charged species. Moreover, the secondary discharge is itself dependent on the plasma operating frequency; more intense discharges are commonly observed with 40 MHz ICPs.…”

87Sr/86Sr isotope ratio analysis by laser ablation MC-ICP-MS in scales, spines, and fin rays as a nonlethal alternative to otoliths for reconstructing fish life history

“…However, sample gas flow pressure and RF power to the plasma may also influence oxide transmission (Horlick et al 1985;Park and Lee 1991;Uchida and Ito 1994). Absolute instrument tuning conditions vary between different laboratories, instrument setups and analytical sessions.…”