Effects of low acetic acid concentrations in inductively coupled plasma atomic emission spectrometry

Abstract

The effects of low acetic acid concentration on selected analytical lines (Mn II, Li I, Cu I, Cu II, Cd I and Cd II) were studied as a function of incident power and carrier gas flow rate, using an ARL 35000 C inductively coupled plasma spectrometer. Line intensity and line-to-background intensity ratios were measured for water and for 3 and 10% acetic acid. The magnitude and mechanism of interference produced by acetic acid were revealed from measured changes in the solution uptake rate, the departure of the ratio of line intensity in acetic acid solution and that in water from unity and the changes in ion-to-atom line intensity ratio. Trace metal determination in 3% acetic acid, used as a 'model' solution in health control of packing materials, and in 9-10% vinegar was carried out by direct aspiration of sample into the plasma at compromise conditions for multi-element analysis (r.f. power, 1200 W and carrier gas flow rate, 0.9 I min-', using matrix-matched calibration standards. Detection limits and relative standard deviation values for Fe, Cu, Cr, Ni, Pb, Al, Cd and Zn were almost equal for aqueous solution and solutions of 3 and 10% acetic acid.

Dilute-and-shoot procedure for the determination of mineral constituents in vinegar samples by axially viewed inductively coupled plasma optical emission spectrometry (ICP OES)

“…The nebulization gas flow rate of 0.6 l min À1 was chosen taking into account the results observed in Figure 1, since it provides better excitation conditions. The Mg II/Mg I ratio obtained with the AX-ICP OES indicates, as expected, that the plasma robustness was improved with an increase in the applied power, for both nebulization systems, as already observed and in acetic acid medium (Roncevic and Siroki 1994;Dubuisson et al 1998a). By applying 1.3 kW the values for the Mg II/Mg I ratio were 10.3 and 10.0 employing the CF-DP and CS-CC systems, respectively.…”

“…The introduction of acid solutions with physical properties different from water in the plasma may modify the characteristics of the aspirated solution and, consequently, the aerosol formation and transport processes. This latter effect is especially critical when organic acids are employed (Roncevic and Siroki 1994;Korn and de Oliveira 1998;Rizzon and Miele 1998;Dubuisson et al 1998a;Ackley et al 1999;Todoli and Mermet 1999;Silva et al 2003).…”

“…Some studies concerning organic acid effects on ICP OES have been presented (Roncevic and Siroki 1994;Korn and de Oliveira 1998;Dubuisson et al 1998a;Ackley et al 1999). Roncevic and Siroki (1994) studied the effects of acetic acid on Mn II, Li I, Cu I, Cd I, and Cd II analytical emission lines using a radial viewed ICP OES.…”

“…Roncevic and Siroki (1994) studied the effects of acetic acid on Mn II, Li I, Cu I, Cd I, and Cd II analytical emission lines using a radial viewed ICP OES. The observed effects in the ICP OES were attributed to the reduction of solution aspiration rate, an increase of the aerosol transport efficiency and changes of plasma excitation conditions.…”

Evaluation of Matrix Effects of Polycarboxylic Acid Introduction in Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES)

“…The rise greater than 5 % was found in higher concentrated acid solutions (>10 %) which was attributed to aerosol formation and transport. 11,23,24 The production of finer aerosol particles and evaporation processes increase the analyte amount as the concentration of acid rise. The mechanism of transport and aerosol formation is connected closely with physical properties of solutions.…”