Decreased intensity of Totalbeam/gases over time in LA-ICP-MS

soohyuna

Hi all,
I was hoping to probe all of your brains for some interesting behaviour we are seeing with LA-ICP-TOF-MS.
I've been using the instrument for the past 1.5 years and we've been seeing this behaviour from get-go.
We run 20um gelatin standard of Blank, 1ppm, 5ppm, 10ppm, 20ppm and 50ppm. This is represented on the attached image. We run 10 lines per standard so that we have 10 blocks..
The issue we are having is this decrease in intensity over time that is quite drastic. We were wondering if anyone run into similar problem.... and if anyone has an idea as to why this might be happening.

Thank you so much!

Bence

Hi soohyuna

Do you see this for ref mats other than the gelatine stds?

-Bence

soohyuna

Hi Bence,

We have only used gelatin standards for reference materials.. although we do use glass NIST 612 to do tuning, we haven't used it as a reference material...