Internal Standard Response Doubling in Samples as Compared to Calibration Standards?

22 May 2020 1 10K Report

Hello,

Please refer to the figure, I have prepared my standard solutions in the range of 10 - 200 ppb, in which the concentration of Internal standard was set to be 50 ppb whose response can be seen in the figure, but as for the case of samples the same amount and concentration of internal standard give me double response as compared to standard. I am looking for the root cause of the problem ,can somebody kindly shares his experience.

Note:

The same problem observed for two systems both for WATERS MS SYSTEM AND AGILENT MS SYSTEM.

There is negligible chance of higher amount of internal standard to be spiked.

Standard and sample solution matrices are same.

Aytul Hamzalioglu

Hi, in our analysis we face the same problem as we get double response when analyzing the samples. Could you find the reason of this problem, or a solution? Thanks

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