Work Package 5:
- Develop advanced surfaces optimized for large-area nanostructured surfaces for SPRi detection
- synthesis of peptides in a high area density
- interaction studies with the peptides
- detection of the interaction with MALDI, SPRi and MOSFET
P4 and P5 will collaborate on large-area nanostructured surface fabrication, which will be optimized to ensure uniform gold nanostructures over the entire surface of glass slides.
The geometry of the nanostructures i.e. the height, shape, and diameter will be optimized to obtain the highest sensitivity and highest spatial resolution with the simplest optical configuration. The surface chemistry enabling peptide synthesis will then be optimized. The two materials that will compose the surface will be selectively functionalized to increase the density of synthesized peptides and sensitivity of detection.
The nano-structuring technique will be optimized to control the distribution and density of a laser desorption matrix on the surfaces. The nano-structuring will be performed prior to or after the peptide synthesis. As an alternative to matrix deposition, the gold nanostructured surface itself will be modified to obtain high ionization efficiency. Nano-hole sizes in the range of 50-400 nm will be tested. The nanostructured surfaces will be designed to support both SPRi analysis and MALDI analysis.
The peptides and their interaction partners require an optimal molecular environment for the intended application. P5, P2 and P6 will define the molecular parameters (thickness, mesh size, type and concentration of immobilization sites) and iterate through preparation and testing of 3D-solid-phase networks until an optimum structure is obtained that allows interaction of the peptides with macromolecules at surface densities suitable for MALDI-IMS.
To guaranty high quality and reproducibility of fabrication of the surfaces developed in WP5, surface analysis will be performed at each steps of fabrication. Protocol of characterization will be developed using state of the art instruments (Ellipsometry, ToF SIMS, XPS etc.)
- P5 is responsible for developing surface coatings
- P6 is responsible for developing 3D surfaces; both for the use in peptide microarray synthesis for subsequent label-free detection
- P2 is responsible for peptide microarray synthesis
- P4 is responsible for performing SPRi analysis
- P3 for performing MALDI IMS analysis and
- P9 for performing MOSFET analysis