A virtual platform to exchange and screen high resolution-mass spectrometry data

Environmental samples are nowadays routinely analyzed by liquid and gas chromatography coupled to high resolution-mass spectrometry (HRMS) detectors from various vendors (e.g. Thermo Fisher Scientific, Agilent Technologies, Bruker, Waters, AB Sciex). A novel platform for archiving and processing raw HRMS data was established by the NORMAN network (www.norman-network.net) to enable inter-comparison of results and increase the level of exploitation of information from HRMS chromatograms. The platform was termed ‘NORMAN Digital Sample Freezing Platform’ (DSFP) as it allows for retrospective screening of the ‘digitally stored’ samples. The DSFP enables fast and effective searching of thousands of substances known or suspected to be present in the environment registered in NORMAN Substance Database (SusDat) and even unknowns across many samples and different matrices. In DSFP, a standardized workflow allows the evaluation of raw mass chromatograms from any HRMS instrumentation vendor after they are converted into the standardized open mzML format. Mass spectral and chromatographic (normalized retention time) information on hundreds up to thousands of components typically contained in each environmental sample is then extracted into spreadsheet-based standardized Data Collection Templates (DCTs). Such 'digitalized' samples can then be retrospectively screened for a presence or absence of virtually any compound detectable by a given LC- or GC-HRMS technique. Concentrations of identified substances can be estimated via a semi-quantification algorithm based on their structure similarity with known chemicals analyzed under the same conditions.  The DSFP was thoroughly tested with data obtained from various European and international projects. Examples of its successful application will be shown on several datasets, including the Joint Black Sea Surveys (JBSS; EU/UNDP EMBLAS-II; http://www.emblasproject.org/), wastewater effluents (SOLUTIONS; http://www.solutions-project.eu/), data from top predators and their prey (LIFE APEX;  https://lifeapex.eu/) and Joint Danube Survey 4 (JDS4; http://www.danubesurvey.org/jds4/about). The latest updates, underlying informatic technologies and key non-target screening functionalities will be presented. The potential of the platform to become a global tool for storing and processing environmental HRMS data will be discussed.

Dr. Nikiforos ALYGIZAKIS (male), is an Analytical Chemist specialized in computational mass spectrometry, database management and non-target screening. He currently focuses on the development of new tools for the identification of contaminants of emerging concern in environmental samples gathered in context of monitoring campaigns (e.g. EMBLAS-II, JDS4) and research projects (e.g. PARC, LIFE APEX, ANSWER). He uses state-of-the-art analytical equipment and cutting-edge data processing tools to analyze LC- and GC-HRMS data. He is part of the core group of the maintainers of the NORMAN Database System and founder of the Digital Sample Freezing Platform, which is a digital archive of mass spectrometry data and enables retrospective suspect screening of thousands of chemicals in the digitally “frozen” data. Through his research, he has demonstrated that the application of retrospective screening of suspected chemicals in digitally “frozen” data has the potential to revolutionize environmental monitoring. He co-authors 44 scientific publications in high-impact international journals (h-18, citations: 1039; Source: Scopus, 04/06/2022).