Identification of phosphonylated peptides using a MALDI target functionalized with lanthanum stearate

Babakov VN1, Gorbunov AYu1, Gladchuk AS2,4, Kalninya YaK2, Shilovskikh VV4, Tomilin NV2, Sukhodolov NG3,4, Radilov AS1, Podolskaya EP2,3
About authors

1 Research Institute of Hygiene, Occupational Pathology and Human Ecology of the Federal Medical Biological Agency, St. Petersburg, Russia

2 Golikov Research Center of Toxicology, St. Petersburg, Russia

3 Institute for Analytical Instrumentation, Russian Academy of Sciences, St. Petersburg, Russia

4 St. Petersburg State University, St. Petersburg, Russia

Correspondence should be addressed: Vladimir Nikolaevich Babakov
Kuzmolovsky, st. Kapitolovo, str. 93, Leningradsraja oblast, Russia; ur.hcepg@vokabab

About paper

Acknowledgments: the authors express their gratitude for technical support to the resource centers Development of Molecular and Cellular Technologies and Geomodel of the Research Park of St. Petersburg State University, and to A.A. Selyutin for the opportunity to use the MALDI mass spectrometer.

Received: 2022-11-11 Accepted: 2023-01-11 Published online: 2023-01-28

As markers of intoxication, adducts of blood proteins with organophosphorus compounds (OPs) allow establishing the fact of poisoning and, furthermore, enable identification of the OPs by the attached residue. This study aimed to develop a method of specific and selective extraction of blood protein adducts carrying OPs on the surface of a matrix-assisted laser desorption/ionization (MALDI) target functionalized with multimolecular structures based on lanthanum stearate using metal affinity chromatography. We have shown the ability of adsorbent to retain both full-size and dealkylated adducts of blood proteins with OPs. The developed method allowed extraction and identification of peptides of human serum albumin and human butyrylcholinesterase modified with various OPs (after incubation of human blood plasma with OPs in concentrations from 1 to 100 ng/mL), which makes this approach applicable for the purposes of OPs identification in the context of investigation of real cases of intoxication.

Keywords: Lanthanum stearate, Langmuir–Blodgett films, serum albumin adducts, butyrylcholinesterase adducts, organophosphorus compounds