Keeping in mind that this study only considered variability due to matrix effect during ionization and a correction for variability in sample preparation and injection volume would still be advisable, we showed that using 2F-AEA as PCIS, LEA, AEA, DHEA, PEA, OEA and 2-AG could be quantified with good accuracy (slope difference with plasma < +/-9%) using a calibration series in neat solution. In this case of severe and variable ion suppression PCIS correction performed even better than the "gold standard" correction with spiked SIL-ISTDs. With the endocannabinoid-related compounds in this study exemplifying a worst-case scenario in terms of matrix effect, the use of PCIS can be extended to other compound classes and other fields analyzing large numbers of analytes, such as exposome research.