The apex Ω desolvating nebulizer is the highest performing ICPMS sample introduction system available. An innovative multistage Peltier-cooled desolvation system combined in series with a helical EPTFE fluoropolymer membrane desolvator simultaneously maximizes ICPMS sensitivity and reduces oxides.
|APX-O||apex Ω high performance membrane desolvation system with quartz spray chamber|
|APX-O-HF||apex Ω HF high performance membrane desolvation system with PFA spray chamber|
High sample transport efficiency over a range of flow rates is illustrated as a linear increase in sensitivity enhancement directly correlated with increased flow rate. Typical sensitivity enhancements of 6x to 10x are observed between flow rates of 100 and 200 µL/min. Highly efficient desolvation over a typical sample flow range for most applications (5–400 µL/min) is illustrated by low oxide formation with no correlation to flow rate.
Using only the Ar sweep and N2 gas flows, the apex Ω is tuned for two different applications, 1) minimum oxide formation (UO+ < 0.02%, 6x sensitivity) and 2) maximum sensitivity improvement (>10x, UO+ < 0.12%,). The apex Ω parameters are saved in the software as condition 1 and 2. Downloading the tune parameters in an alternating fashion (every ~ 2 mins) demonstrates immediate return of sensitivity, stability and oxide levels to previous conditions. Saving application specific tuning conditions reduces setup time and improves ease of use.
apex Ω stability is illustrated as both, 1) Indium signal intensity for the quartz and HF (PFA) models and 2) Nd isotope ratio precision for the quartz model. The Ω and HF versions have near identical sensitivity and long term stability (<1% RSD for > 8 hrs). Signal stability is translated into isotope ratio precision (repeatability) of less than 13 ppm (2 RSD).
Replicate injections illustrate greater than four orders of magnitude (10,000x) washout is achieved in 1 minute for Nd. Two percent HNO3 is used to achieve 10,000x washout for Li and Nd, whereas, classic memory prone elements such as Th are washed out similarly with 1% HF.