Project: Comprehensive two-dimensional liquid chromatography mass spectrometry (LCxLC-MS) method for Water Treatment Monitoring (WP3)
Host institution: KU Leuven
Supervisor(s): Deirdre Cabooter, Raf Dewil (PhD promoters)
Objectives: To develop a highly sensitive LCxLC-MS method for the screening of Contaminants of Emerging Concern (CECs) and their degradation products in environmental water pre- and post-treatment. Since the nano-photocatalysts developed in WP1 will result in a plethora of degradation products (DPs), identifying these DPs from a chemical and ecotoxicological point-of-view is crucial to assess the true potential of these nano-based degradation techniques. Since DPs display a variety of physicochemical properties, a single liquid chromatography (LC) method is inadequate to resolve all DPs in treated water samples, mandatory for their identification with MS. By physically combining two complementary LC methods in a two-dimensional (2D) LC separation, compounds that are insufficiently separated on a first LC column, can be redirected to and further separated on a second LC column, improving the resolution of the separation. Comprehensive 2D-LC (LCxLC) implies the entire eluent of the first dimension column is redirected to the second dimension in small, consecutive fractions, resulting in the highest possible peak capacities. The best results in LCxLC are obtained when combining two orthogonal LC methods, that result in uncorrelated retention times, such as reversed-phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC). Orthogonal LC methods typically require mobile phases with opposite elution strengths, making their online combination challenging. To deal with this problem, DC13 will develop and investigate novel approaches to combine orthogonal columns in LCxLC, and benchmark these to other modulation strategies in LCxLC, such as active solvent modulation. The LCxLC system will be combined with high-resolution mass spectrometry for detection and identification. The system will be developed for a representative sample of 30-50 pharmaceuticals, frequently encountered in the environment. Once an optimized system is available, it will be applied to various real-world samples.
Expected results: Improved LCxLC-MS methodology for the detection of CECs and degradation products at nanomolar concentrations or less.
Planned secondments:
- UNISA (Sup.: L. Rizzo): M24-26 (3 months): Obtain degraded CECs in urban wastewater using NTP in combination with NCMs and elucidate samples using LCxLC-MS method.
- NORG (Sup.: Sergei Shaposhnikov): M28-30 (3 months): Obtain understanding in in vitro assays of samples post-exposure to NMs, to correlate structure of degradation products to their cytotoxicity and genotoxicity.
Enrolment in Doctoral degree: KU Leuven Doctoral School Biomedical Sciences (BE)
