# Continuous Flow Paper Spray Ionization Mass Spectrometry for In-Depth Characterization of Anticancer Drugs in Tissues: Addressing Mass Spectral Complexity

## TL;DR

A new mass spectrometry method detects and measures anticancer drugs in tissue samples, revealing how drugs are absorbed and their complex chemical behavior.

## Contribution

CFPSI MS enables semiquantitative analysis of anticancer drugs in tissues with continuous flow of internal standards.

## Key findings

- Palbociclib showed the highest bioabsorption in tissue samples compared to copanlisib and olaparib.
- Tandem mass spectrometry revealed significant in-source chemical reactivity and spectral complexity of the drugs.
- The study emphasizes the need for careful spectral interpretation in complex biological matrices.

## Abstract

We
introduced continuous flow paper spray ionization mass spectrometry
(CFPSI MS) for the rapid detection and characterization of anticancer
drugs in solid tissue samples. CFPSI is a paper spray-based semiquantitative
method using continuous flow of an internal standard to quantify the
amounts of drugs released from the tissue samples. Using patient-derived
xenograft (PDX) mouse model tissue samples, we observed differential
absorption of three anticancer drugs, palbociclib, copanlisib, and
olaparib. Palbociclib was found to be bioabsorbed in the tissue samples
to the largest extent. Tandem mass spectrometric analysis explored
the in-source chemical reactivity of these drugs, leading to significant
spectral complexity. Our findings highlight the importance of careful
spectral interpretation in complex biological matrices and support
the development of future rapid quantitative CFPSI analysis of these
drugs in tissue samples.