I was hoping to get some advice on how to apply some of the 5100 VDV OES features to assist in my method development work, i.e. Intelliquant, Trend analysis, Confirmatory wavelengths. I think I've already a fair idea of how to apply these tools but it would be great to receive some feedback to ensure I'm on the right track.
This feature located on the analysis tab provides trend information on the Argon Intensity and Nebuliser back pressure during a full quantitative analysis. I would think the feature would be useful as follows:
1. Identifying a suitable sample dilution factor. For example, if using a dilute & shoot method to analyse Serum samples, the Nebuliser pressure monitor may show that higher argon pressure is needed to push through samples diluted 1:20 compared with samples diluted 1:50 and 1:100. An increasing neb. pressure could predict a possible blockage from low dilution samples since they haven't been digested. Would this be a correct application?If so, what is a desirable nebuliser pressure to maintain?
2. Using the Argon Intensity monitor again to determine 1) suitable sample dilution, i.e. a high matrix sample at a 1:20 dilution may cause greater plasma cooling effect than samples diluted 1:50 and 1:100 and therefore lowering the energy required to excite the analyte electrons, possibly giving falsely low results. 2) atypical samples which have a different matrix composition than typical samples causing a large fluctuation in the argon intensity. Would this be a correct application? If so, how large of an intensity fluctuation would be considered significant?
When using 2 wavelengths for various elements - primary and confirmatory, how big of a difference in concentration values between them would be significant or indicative of an interference? For example, primary reads 1.00 ppm and confirmatory reads 0.98 or 102 ppm, I assume this is just acceptable variation but a primary reading of 1.00 ppm and a confirmatory reading of 0.45 ppm or 2 ppm, would indicate some interference even if its not visible on the spectral view? Would this be a correct interruption?
Calibration Curve Linearity Challenge:
To test if the calibration curve range chosen for your standards is linear, is it acceptable to challenge the curve by running the same standards against the curve as 'samples' in a randomized order. If you are getting back close to the known concentration then its a sign that the curve range is linear? Apart from a r2 value of close to 1.0.
I presume using single element standards is more appropriate than a multi-element to rule out interference but when you move on to using a multi-element standard what tests could you try to check if the linearity hasn't been impacted by the multi-elements? Possibly running the multi-element standards as randomized samples maybe . . . .
I appreciate the feedback