Abstract | Mass spectrometry has reached a broad diffusion as a diagnostic tool in many branches of life sciences and analytical chemistry. In the field of elemental analysis, inductively coupled plasma mass spectrometry (ICPMS) has become the standard technique for performing quantitation of elements at the ultratrace level. In a typical analysis, the ICPMS response of standard solutions is first acquired and plotted against concentration. Then, the calibration curve is obtained by linear fitting and is used to calculate analyte concentration in the samples. In mass spectrometric analysis, one must bear in mind that the detector responds to the isotopes of an element and not to the element itself. For example, in the case of lead, the analyst can choose to acquire m/z of 204 (²⁰⁴Pb), 206 (²⁰⁶Pb), 207 (²⁰⁷Pb), or 208 (²⁰⁸Pb). Usually, quantitation is obtained on m/z 208, which corresponds to the most abundant isotope in the mass spectrum of lead (Fig. 1). |
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