The Apex Omega desolvating nebulizer is the highest performing ICPMS sample introduction system available. An innovative combination of a multistage Peltier-cooled desolvation system in series with a helical EPTFE fluoropolymer membrane desolvator simultaneously maximizes ICPMS sensitivity and minimizes oxides.
|APX-O||Apex Omega high performance membrane desolvation system with quartz spray chamber|
|APX-O-HF||Apex Omega 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 Omega 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 Omega 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 Omega 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.