Reduction of polyatomic ion interferences in inductively coupled plasma mass spectrometry by cryogenic desolvation

Abstract

Multiple desolvatlon steps at -80 °C for a continuous-flow ultrasonic nebulizer reduced the load of water and HCI on an argon inductively coupled plasma (ICP). Consequently, the oxide ratios MO+/M+ for Ca, Mo, and La were 0.02-0.05%.Polyatomic Ion Interferences from ArO+, CIO+, and ArCI+ were also reduced by several orders of magnitude. Measured Isotope ratios for Nl, Cd, and Fe were In good agreement with accepted natural values, and the detection limits were 2-20 ng L'1 for Nl, Fe, V, As, and Cd In the presence of concentrated matrices of HCI, Ca, or Mo that would normally cause polyatomic Ion Interference. Eight additional seconds were necessary for sample rinse-out, and analyte sensitivity was reduced by a factor of 2 when cryogenic desolvatlon was used. UO+/U+ ratios were reduced to 0.06% when cryogenic desolvatlon was used and acetylene was added to the central channel. Sodium matrices up to 100 mg L1 decreased the La+ count rate but did not affect the oxide ratio LaO+/La+. At 1000 mg L~1 NaCI the LaO+/La+ ratio Increased to 0.08%.

Geoanalysis using plasma spectrochemistry ? milestones and future prospects

“…The abundance of these species is controlled by the aerosol carrier gas flow rate, plasma operating power, and ion lens configurations. Mass spectral interferences are derived from the argon support gas and entrained atmospheric gases ( 40 Ar + , 40 Ar +40 Ar + , 40 [58,59] and addition of nitrogen [60]. The addition of 1% nitrogen to the coolant Ar gas flow at a nebulizer gas flow rate of 0.95 l/min dramatically reduced 40 Ar 35 Cl + and 35 Cl 16 O + without the loss of sensitivity of the analyte ions.…”

Comparison of microconcentric and membrane-desolvation sample introduction systems for determination of low rare earth element concentrations in surface and subsurface waters using sector field inductively coupled plasma mass spectrometry

“…In general detection limits are substantially improved with decreasing spray chamber and increasing heating stage temperatures. Overloading has also been minimized by desolvating the aerosol using crycondensers which were cooled by dry ice to −77°C [31][32][33][34].…”

The Matrix Effect of Biological Concomitant Element on the Signal Intensity of Ge, As, And Se in Inductively Coupled Plasma/Mass Spectrometry

“…1,2 The accuracy of As and Se determinations is well known to be seriously affected by the occurrence of spectral interferences, [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] as the resolution of quadrupole mass spectrometers is not sufficient to resolve atomic and molecular species having the same nominal mass. But recently, spectral interferences has been overcome by collision cell or dynamic reaction cell.…”