The Next-Generation Life Marker Chip: A Photonic Biosensor for Space Exploration

Building upon the heritage of the Life Marker Chip (LMC) developed for Mars exploration (Sims et al. 2012), I present an advanced integrated photonic biosensor for in-situ molecular detection in space environments. The system employs an asymmetric Mach-Zehnder Interferometer (aMZI) fabricated using silicon nitride waveguide technology, enabling label-free detection of biomolecules through refractive index sensing. Material-selective surface functionalization allows targeted immobilization of probe molecules exclusively on the waveguide sensing areas, enhancing sensitivity - down to ppt levels - and specificity. I demonstrate the successful detection of multiple biomarkers with this novel system, including DNA and polycyclic aromatic hydrocarbons, as well as selectivity of chiral enantiomers of the amino acid phenylalanine (Ligterink et al. in prep.).

Next, I will outline the future development of the LMC. By integrating light sources, detectors, and microfluidic sample handling on a single chip, the size and complexity will be reduced compared to previous systems. The compact, integrated design eliminates the need for external optical components while maintaining high sensitivity, making it particularly suitable for space applications where size, mass, and robustness are critical. This work represents a significant step toward developing field-deployable molecular detection capabilities for planetary exploration.

 

Sims et al. 2012: Sims, M.R., Cullen, D.C., Rix, C.S., Buckley, A., Derveni, M., Evans, D., García-Con, L.M., Rhodes, A., Rato, C.C., Stefinovic, M. and Sephton, M.A., 2012. Development status of the life marker chip instrument for ExoMars. Planetary and Space Science, 72(1), pp.129-137.