1. The study investigates using mass spectrometry imaging (MSI) as a quantitative drug analysis technique by developing a methodology for absolute quantification of compounds in tissue sections.
2. The methodology involves calculating tissue extinction coefficients, generating calibration curves from drug standards on tissue, and using the curves to quantify drug levels in tissue sections from preclinical studies of three drugs.
3. The developed quantification MSI (qMSI) technique was validated by comparing quantified drug levels in tissues to levels obtained using other quantitative methods such as liquid chromatography-mass spectrometry, showing good agreement.