| 摘要 |
PROBLEM TO BE SOLVED: To provide an ion trap mass spectroscope that can reduce an effect of space charge in an ion trap and secure high mass precision and mass resolution without inducing increase of the measurement time, consumption of samples, reduction of detection sensitivity, etc., and a mass spectroscopic method using the ion trap mass spectroscope.SOLUTION: After data of the whole m/z range or a predetermined m/z range are obtained (S5), a mass spectrum integrated in the data which have been obtained until that time is determined (S6), and an S/N ratio is calculated for each peak detected on the spectrum (S7 and S8). The S/N ratio of each peak is compared with a threshold value (S9 and S10), and a measurement condition is changed (S11) so that the m/z range corresponding to peaks having S/N ratios which are less than the threshold value are excluded from an m/z range as a measurement target (S11). When the measurement is repeated while changing the measurement condition, the measurement of the m/z range containing faint ion peaks with low S/N ratio has been executed till the last. Therefore, the measurement with high precision, high resolution and high sensitivity can be performed with reducing the effect of the space charge while reducing needless measurements. |
