18th International Symposium on Hyphenated Techniques in Chromatography and Separation technology - Abstract Book

Hyphenated Techniques in Chromatography and Separation Technology — Leuven 2024 Abstract Book: Expert Summary

Significance of the topic

• Hyphenated chromatographic techniques (LC-MS, GC-MS, GC×GC, SFC-MS, CE-MS, IMS, etc.) remain central to modern analytical chemistry because they provide the selectivity, sensitivity and structural information required for complex matrices across environmental, pharmaceutical, clinical, food and industrial applications.
• Current conference themes emphasize two urgent directions: (i) improving analytical performance (speed, resolving power, isomer separation, structural ID) and (ii) increasing sustainability and automation (greener solvents, solvent reduction/recycling, automated sample prep and QA/QC, AI-driven data handling).
• Integration of orthogonal separations (multidimensional chromatography, ion mobility) with high-resolution detectors and computation (Bayesian statistics, machine learning, predictives) is expanding capabilities for non-target screening, structural elucidation and routine high-throughput workflows.

Objectives and overview

• This Abstract Book collects plenary, keynote, oral and poster contributions that present methodological advances, case studies and instrument innovations aimed at: enhancing quantitative and structural characterization, greening preparative and analytical separations, applying AI and computer vision to multidimensional data, and developing robust workflows for regulatory and clinical contexts.
• Representative goals addressed include: enabling RID detection with temperature-programmed LC; greener peptide purifications (MCSGP and alternative solvents); AI-assisted interpretation of GC×GC-MS volatilomes; non-targeted environmental and wastewater screening with TIMS and LC-/GC-HRMS; improved oligonucleotide and mRNA analytics; and novel sample preparation (needle-trap devices, aptamer sorbents, 3D-printed sorbents).

Methodology and instrumental approaches

• Separation techniques: Isocratic and gradient LC (RPLC, HILIC, IP-RPLC), comprehensive 2D chromatography (LC×LC, GC×GC, RPLC×SFC), supercritical fluid chromatography (SFC) including UHPSFC, capillary electrophoresis (CE, MEKC, NACE), and temperature-responsive LC (TRLC).
• Mass spectrometry and orthogonal detectors: quadrupole and QTOF HRMS, Orbitrap and FT-ICR, triple quadrupole MS/MS, TIMS/SWIM, cyclic IMS, ion mobility–MS (IMS-MS) for CCS-based annotation, infrared ion spectroscopy (IR-IS) and REIMS for rapid tissue analysis.
• Sample handling and front-end innovations: needle-trap devices (NTDs, FI-NTDs), solid-phase extraction (including multi-fraction SPE for polarity range), immobilized enzyme reactors (IMERs) for rapid digestion, microfluidic membrane-based ion-strippers for ion-pair removal, 3D-printed functional sorbents, stir-bar sorptive extraction with ionic-liquid coatings, and direct-injection high-throughput LC-MS.
• Data processing and modelling: AI (computer vision, augmented visualization) for GC×GC pattern recognition; Bayesian frameworks for chromatographic automation and peak assignment; ANN and multilinear regression for SFC-MS make-up-solvent prediction; chemometrics, random forests and multivariate time-series analyses for non-target prioritization.

Used instrumentation (consolidated list and roles across studies)

• High-resolution MS tools: Orbitrap (incl. HR/AM applications), FT-ICR MS, QTOF, triple quadrupole MS/MS for targeted quantification.
• Ion mobility platforms: Trapped IMS (TIMS, SWIM), cyclic IMS, TWIMS — used for isomer separation, CCS reference building and drift-time filtering to clean spectra.
• Chromatography platforms: UHPLC/nanoLC (including bioinert columns), µPAC micro-pillar array columns, UHPSFC systems (e.g., Waters UPC2), GC×GC systems (with FID, qMS, TOF, VUV detectors), SFC-FTICR and SFC-qTOF couplings, TD-GC-HRMS (Orbitrap) for gas-phase non-target analysis.
• Specialized sampling & front-end devices: Needle-trap devices (NTDs, FI-NTDs), SBSE with IL coatings, thermal desorption units, microreactor–MS hyphenation with switching valves, online IMERs, membrane microfluidic ion strippers, robotic liquid-handling stations for isotope-dilution CRM production.

Main results and discussion (selected highlights)

• RID compatibility with gradients achieved via temperature-responsive LC (TRLC): Using LC stationary phases based on lower critical solution temperature polymers allows use of water-only mobile phases and temperature gradients; TRLC delivers overlapping calibration responses among similar compounds and enables RID quantification for non-UV analytes (free fatty acids, long-chain alcohols).
• Greener preparative peptide purification: Replacing acetonitrile with greener modifiers (ethanol, isopropanol, dimethyl carbonate) and adopting multicolumn countercurrent solvent gradient purification (MCSGP) drastically reduced solvent consumption (e.g., >80% reduction for icatibant) while maintaining purity/throughput.
• AI + GC×GC advances: Computer vision and augmented visualization correct retention shifts and enable comparative pattern recognition, improving detection and prioritization of food odorants, volatilome markers and aroma fingerprinting; AI-smelling prototypes predict sensory signatures from multidimensional GC×GC-MS data.
• Structure ID without large NMR amounts: Multi-modal MS techniques (advanced fragmentation modes, H/D exchange, IR-IS) combined with quantum chemical predictions and ML allow robust assignment of drug metabolites and positional isomers, reducing reliance on NMR for many cases.
• Ion mobility benefits for non-target and isomer resolution: TIMS and SWIM modes greatly enhance resolving power, enabling cleaner spectra for low-abundance halogenated contaminants and better annotation confidence via CCS orthogonal matching.
• SFC-MS and make-up solvent optimization via ANN: Extensive screening (25 make-up solvents, 207 molecular descriptors across 60 analytes) plus ANN modelling enabled rational selection of make-up solvent and ion source settings to maximize ESI/APCI response and reduce optimization time and solvent use.
• Needle-trap device evolution: FI-NTDs and other NTD variants provide exhaustive, robust, green sampling for volatiles and aerosols, compatible with benchtop and portable GC, and amenable to on-site use with simple calibration and minimized analyte loss.
• Non-target environmental/wastewater workflows at scale: High throughput direct-injection LC-MS/MS and LC-HRMS workflows analyzed >2000 wastewater samples and performed suspect screening (library of ~1219 compounds) yielding hundreds of detections per sample and enabling spatiotemporal monitoring and prioritization for WBE applications.
• Clinical & diagnostic translation of MSI and REIMS: Mass spectrometry imaging and REIMS support single-cell lipid/protein mapping, intra-operative tumor typing and prognosis; approaches demonstrate quasi-real-time tissue characterization for surgical guidance and biomarker discovery.
• Advances in oligonucleotide and mRNA analysis: IP-RPLC, HILIC and bioinert columns, short high-throughput columns, pressure tuning, and IMER-coupled online digestion strategies improved sensitivity, throughput and selectivity for ONs and mRNA structural characterization (5′ cap, poly-A, dsRNA, modifications).
• µPAC column generation 2.0: Second-generation micro-pillar array columns (halved pillar size and spacing) showed intrinsic performance gains and new pillar geometries improved radial mixing and reduced side-wall effects, pertinent to nano-/micro-flow proteomics.
• Bayesian approaches for chromatographic automation: A paradigm shift toward probability-based decision support (Bayesian peak detection, deconvolution and model averaging) allows informed operator decisions and robust automation of complex datasets (2D chromatography, LC-MS).
• Sustainability & green metrics: Multiple contributions advanced solvent substitution (Cyrene as biodegradable high-boiling solvent), reduced solvent volumes (SFC for preparative separations), and method greenness assessment via AGREE and lifecycle thinking for analytical labs.

Benefits and practical applications

• Regulatory and environmental monitoring: Robust non-target screening workflows (LC-/GC-HRMS + IMS/TIMS) and chemometric prioritization support contaminant discovery, compliance checks and wastewater-based epidemiology at scale.
• Pharmaceutical development and QC: Integrated multidimensional platforms (ProtA + IMER + orthogonal chromatographic modes) permit comprehensive antibody CQAs from single injections; QbD-driven automated method development accelerates impurity resolution with high assurance.
• Food and flavor industry: Advanced aroma profiling (SPME/DHS/SBSE + GC×GC-TOFMS) with AI-assisted pattern recognition improves raw-material selection, off-flavor detection, product reformulation and sensory prediction for alternative proteins and fermentation-derived ingredients.
• Clinical diagnostics and intra-operative decision support: MSI and REIMS-based rapid tissue phenotyping enable near-real-time diagnostics, tumor border visualization and potential prognostic assessments to guide surgical decisions.
• Materials and fuel testing: GC×GC coupled detectors and probabilistic property models support prescreening of sustainable aviation fuels, plastic pyrolysis oils characterization (PPOs), and tyre composition/off-gassing assessments relevant to environmental risk and process design.
• Sample preparation and field monitoring: NTDs, aptamer-based oligosorbents, and 3D-printed sorbents provide portable, selective, and green sample collection methods for environmental air, breathomics and targeted bioanalysis.

Future trends and application possibilities

• Deeper integration of AI and ML: Expect broader adoption of computer vision for chromatogram alignment, ML models for ion-source/make-up solvent prediction, and deep-learning-assisted structural annotation for HRMS + IMS data.
• Increased adoption of IMS/TIMS: Collision cross-section databases and high-res mobility will become routine orthogonal identifiers for both targeted and non-target workflows, improving isomer discrimination and annotation confidence.
• Miniaturization and perfect-order media: µPAC and other microfabricated separation media will expand, especially for nano-flow proteomics and on-line hyphenation to high-sensitivity MS, lowering extra-column dispersion and boosting efficiency.
• Green chromatography mainstreaming: Wider use of SFC (analytical/prep), alternative green solvents (DMC, Cyrene), solvent-recycling workflows and method greenness metrics will be required by industry and regulators.
• Probabilistic automation & open toolchains: Bayesian and probabilistic frameworks will be more frequently embedded in data-processing pipelines to deliver uncertainty-aware results and decision-support rather than single-point automated calls.
• Convergent multimodal analytics: Hybrid workflows combining chromatography (multi-D), IMS, IR-IS and orthogonal detectors plus computational prediction (quantum chemistry, ML) will minimize reliance on large-scale NMR and speed structure confirmation.

Conclusion

• The Leuven 2024 symposium contributions illustrate that hyphenated separation science is evolving along two synergistic axes: technical performance (multidimensional separations, ultra-high-resolution detection, ion mobility) and operational maturity (greener workflows, automation, AI-driven data interpretation).
• Practical uptake of these developments is already visible across environmental monitoring, pharmaceutical QC, food aroma and clinical diagnostics. Continued cross-disciplinary efforts—combining instrument design, sample-prep innovation, data science and sustainability metrics—are essential to translate these advances into routine, regulatory-robust practice.

Representative references (selected from the Abstract Book)

• Baert M., Wicht K., Hou Z., Szucs R., Du Prez F., Lynen F. Exploration of the Selectivity and Retention Behavior of Alternative Polyacrylamides in Temperature Responsive Liquid Chromatography. Anal. Chem. 92 (2020) 9815–9822.
• Bandini E., Wicht K., Ampe A., Baert M., Eghbali H., Lynen F. Hyphenating temperature gradient elution with refractive index detection through temperature-responsive liquid chromatography. Anal. Chim. Acta 1231 (2022) 340441.
• Caratti A., Fina A., Trapani F., Bicchi C., Liberto E., Cordero C. Artificial Intelligence Sensing: Effective Flavor Blueprinting of Tea Infusions for a Quality Control Perspective. Molecules 29 (2024) 565.
• Müller B. H., Scholl G., Far J., De Pauw E., Eppe G. Sliding Windows in Ion Mobility (SWIM): a New Approach to Increase the Resolving Power in Trapped Ion Mobility-Mass Spectrometry Hyphenated with Chromatography. Anal. Chem. 95 (2023) 17586–17594.
• Sadighi R., de Kleijne V., Wouters S., Lubbers K., Somsen G.W. Online multimethod platform for comprehensive characterization of monoclonal antibodies in cell culture fluid from a single sample injection. Anal. Chim. Acta 1287 (2024) 342074.
• Pawliszyn J. Recent Developments in Needle-Trap Technology: An Effective Exhaustive Microextraction Technology Facilitating Hyphenation of Sampling/Sample Preparation to Gas Chromatography. Trends Anal. Chem. 153 (2022) 116643.
• Devaux J., et al. SFC-FTICR and RPLC×SFC-qTOF for the characterization of advanced bio-oils. J. Chromatogr. A 1697 (2023) 463964.