My name is Azam Noori. I am an assistant professor at Merrimack College. We have purchased an ICP-MS lately. It is NEXION 350X (Perkin Elmer). I am working with plants. I analyzed some samples yesterday. The calibration curve for most elements was good (Correlation factor: 0.998-0.999).
The concentration of elements in the first 5 samples was reasonable. Then I used the standard 10ppb as a sample to make sure the instrument is reporting the correct concentration. The concentration of most elements was much higher than 10 ppb in this sample. For example for silver (109), it was 623 ppb while when same sample was used as a standard the concentration was 9.88 ppb. I analyzed some samples after this, and the concentration of most elements (Ag, Mo, Cd, Sn, As, Ni, Fe, Cr, Pb, and V) in all samples were negative. It is not what I expected. Do you have any suggestions for troubleshooting?
Azam Noori, Ph.D.
Department of Biology
315 Turnpike Street
North Andover, MA 01845