Volume: 5, 2026
5th International PhD Students’ Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: H017
DOI: https://doi.org/10.24326/ICDSUPL5.H017
Published online: 22 April 2026
Friend or foe? Application of the transient matrix effect in blood opioid analysis
Krystian Siwek* and Michał P. Dybowski
Department of Chromatography, Institute of Chemical Sciences, Maria Curie Sklodowska University in Lublin, 3/202 Maria Curie-Skłodowska Sq., 20-031 Lublin, Poland
* Corresponding author: krystian.siwek@mail.umcs.pl
Morphine is a potent opioid characterized by a narrow therapeutic index, meaning that even minor deviations in its blood concentration can result in severe toxicity or profound pharmacological effects. Due to its frequent involvement in instances of drug abuse, as well as the necessity for strict therapeutic monitoring and forensic investigations, the accurate, trace-level determination of morphine in the bloodstream is absolutely crucial. However, the quantitative analysis of opioids in complex biological matrices like whole blood frequently suffers from matrix effects, traditionally considered as an analytical problem that causes signal suppression, variability, and reduced accuracy. This study challenges that paradigm by utilising so-called transient matrix effect (TME) as a powerful analytical tool. Focusing on morphine as a representative opioid, we developed a gas chromatography-tandem mass spectrometry (GC-MS/MS) method combined with the QuEChERS extraction technique. Instead of attempting to eliminate the matrix effect, high-boiling protectants were introduced to modify the physicochemical environment of the analyse during the injection and chromatographic retention stages. Under optimized conditions – specifically using acetonitrile as a solvent, a high injector temperature (300 °C), and a low initial column temperature (40 °C) to promote analyte focusing at the beggining of the column – the intentional induction of TME yielded remarkable sensitivity improvements.
Among the evaluated protectants, long-chain amines (C18-NH₂) increased the analytical signal for morphine by an astonishing 1080%, while polyethylene glycols (PEG-600) provided a robust 628% enhancement compared to unmodified reference samples. To validate the practical applicability of this phenomenon, the method was tested on authentic forensic whole blood samples. Even in the presence of residual co-extracted biological matrix components, the addition of PEG-400 resulted in a 177% signal enhancement for morphine without requiring any modifications to the extraction protocol. These findings demonstrate that when properly controlled, the transient matrix effect is a highly effective tool for trace-level opioid detection, ultimately increasing sensitivity of routine toxicological analyses.
Keywords: morphine; GC-MS/MS; transient matrix effect
How to cite
Siwek K., Dybowski M.P., 2026. Friend or foe? Application of the transient matrix effect in blood opioid analysis. In: 5th International PhD Students’ Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL5.H017