Lab-in-Droplet platform for glycoprotein biomarker discovery: from device conception towards diagnostic applications – DropLab

1) Conception of the open-mode digital capillary electrophoresis (DCE) system with sequential injection analysis
2) DCE separation of human transferrin (Tf) glycans after N-deglycosylation
3) Droplet-wise sample treatment for release and fluorescent labeling of Tf glycans
4) Lab-in-Droplet platform development for Tf glycan patterns mapping

1) A new modular capillary electrophoresis instrument that can be constructed from different off-the-shelf microfluidic, optic and electrophoretic module. This instrument can be adapted to injection and separation of analytes from a tiny droplet.
2) A new capillary electrophoresis method with on-line preconcentration of oligossacharides that is more performing than the commercial kit (in terms of signal intensity and peak capacity).

In terms of innovation, the Lab-in-Droplet platform will provide a novel tool for elucidation of glycosylation patterns, as well as the meso-scaled DCE that may fill the gap still little explored between bench-top and lab-on-chip CE instrumentation. In terms of impacts from a wider application scope, the Lab-in-Droplet will provide a faster approach to discover new glycosylated biomarkers for different diseases causing heavy social and economic burdens (cancers and cardiovascular diseases for instance). It also leads to development of new diagnostic tools facilitating patient management and reduction of healthcare costs via better treatment follow-up and more accurate diagnoses. The Lab-in-Droplet platform fits perfectly to a new potential market for inexpensive and unsophisticated analytical devices.

1. Analytica Chimica Acta, Volume 1143, 2021, Pages 281-297
2. Analytica Chimica Acta, Volume 1135, 2020, Pages 47-54
3. The 36th International Symposium on Miscoscale Separations and Bioanalysis MSB 2020 - Oral presentation
4. The 26th international symposium on electro- and liquid phase separation techniques - ITP 2019 - Oral presentation
5. Application note on the website of Fluigent - the leading company worldwide in microfluidics

This project aims to develop a novel analytical platform, named Lab-in-Droplet, which integrates i) magnetic bead-based sample treatment in droplets and ii) droplet-interfaced capillary electrophoresis, hereby named ‘digital CE’ (DCE). This Lab-in-Droplet will unprecedentedly offer both efficient sample treatment and resolute analytes separation within sub µL droplets. This will be the first platform able to couple sample treatment and analyte separation modules without any problem of working volume mismatch, thus solving the instrumental and methodological bottlenecks currently encountered in analytical module integration. To demonstrate the applicability and significance of the Lab-in-Droplet, the platform will be applied for mapping the glycan patterns of human transferrin (Tf), serving for diagnosis of chronic alcohol abuse and for the screening of Congenital Disorders of Glycosylation (CDGs). The magnetic-bead based sample handling module will serve for N-deglycosylation, on-beads fluorescent labeling of glycans prior to mapping of glycans with DCE. In a larger application scope, the Lab-in-Droplet platform will provide a novel tool for elucidation of glycosylation patterns, serving for both biomarkers discovery and pathogenesis unraveling. Our long-term research goal is to convert the novel Lab-in-Droplet concept into a robust, high throughput and versatile tool for selective and sensitive analyses of various biomarkers, notably glycopeptides and glycoproteins in biological matrices. This tool will be established in a meso-scaled format, i.e. the configuration in between bench-top and microchip-based instruments, with a full automation feature in order to bring robustness and transportability into the same bioanalytical device. Different work packages are anticipated to guarantee a smooth advancement of the project, including i) Conception of the open-mode DCE system with sequential injection analysis (SIA), ii) DCE separation of human transferrin (Tf) glycans after N-deglycosylation; iii) Droplet-wise sample treatment for release and fluorescent labeling of Tf glycans and iv) Lab-in-Droplet platform development for Tf glycan patterns mapping. Via the implementation of the proposed research, a multidisciplinary collaboration network will be fostered, with the strategic partner from Hopital Bichat (Paris), and collaborators from Institute Curie (Paris) and University of Basel (Switzerland). The project, while being in-line with the main research interest of the project coordinator’s group in electrokinetic methodology development and protein/peptide-based biomarker discovery and analysis, will bring a new expertise in DCE and droplet-based sample treatment, helping the host group rest competitive in research worldwide. In terms of innovation, the Lab-in-Droplet platform will provide a novel tool for elucidation of glycosylation patterns, as well as the meso-scaled DCE that may fill the gap still little explored between bench-top and lab-on-chip CE instrumentation. In terms of impacts from a wider application scope, the Lab-in-Droplet will provide a faster approach to discover new glycosylated biomarkers for different diseases causing heavy social and economic burdens (cancers and cardiovascular diseases for instance). It also leads to development of new diagnostic tools facilitating patient management and reduction of healthcare costs via better treatment follow-up and more accurate diagnoses. The Lab-in-Droplet platform fits perfectly to a new potential market for inexpensive and unsophisticated analytical devices. Technology transfer is therefore anticipated, in the hope to convert the research prototype of Lab-in-Droplet into a commercial product.