Dear Igor

The plain answer is no. Most ICPMS allow you to set specific dwell times per isotope. A posteriori it is thus not possible to "guess", which have been used.

I can imagine that many labs use the same dwell (+ settling) time per isotope as default but that's not clear from the data alone.

Best,

Bodo

Dear Bodo Hattendorf

Thank you for the answer. It is what I was afraid of, I was hopeful though if there was any formula that would involve the analyte mass and the sweep dwell time.

I was trying to implement the Pettke et al. (2012) Limit of Detection calculation, which relies on the analyte dwell time. Without this information, it sadly won't be possible.

Well, thinking abiut it, you may get an idea by looking at the blank signals. If they are low enough, the cps will be integer counts divided by the dwell time in seconds. So if the blank signal is lots of 0s and once in a while its 100cps, the dwell time is likely 10 ms.

It sounds interesting, Bodo Hattendorf. Is there any reason for that you can tell me?

Dear Igor

At low intensity, just a single (or a few) ion(s) may be registered during the dwell time of the MS. If there was just one ion within a dwell time of 10 ms, the resulting intensity in counts per second (cps) is 100. For 20 ms dwell it would be 50 cps. Some instruments may include settling times or correct for detector dead time, which can lead to different readings. But if there is many zero cps readings in the blank and occasionally cps that are multiples of a specific value, the lowest of the non-zero values is likely the inverse of the dwell time in seconds. In other words: the result of a single ion registered.

Hope this helps

Bodo

Dear Bodo

Sure it helped. Thank you, mate.