Silicon nanophotonics for multi-omic marine detection

Photosynthetic microorganisms, central to Earth’s carbon cycle, can form dense blooms that release biotoxins contaminating drinking water sources. Correlating how physico-chemcial drivers impact expression of metabolites remains a challenge, in part, due to the constraints in extending techniques like mass spectroscopy and sequencing to remote in-situ marine environments. Advances in remote vehicles now enable in situ measurements of temperature, pH, and fluorescence. Similar measurements of metabolites and nucleotides are critical but current in situ sensors are limited by low sensitivity, dynamic range, and scalability. Here, we present our approach based on silicon nanophotonics to simultaneously and rapidly measure multiple ‘omic’ signatures from water samples. Our nanoantennas are composed of sub-wavelength silicon nanoblocks that resonantly trap and strongly amplify the electromagnetic field intensity in a 15 micron sensing ‘pixel’. Thousands of resonator pixels can be fabricated as individually addressable elements and read out simultaneously on a simple CCD array. Molecular binding through self-assembled monolayers generates small perturbations to the local dielectric environment, strongly shifting the optical resonance. We use this platform to demonstrate quantitative, amplification-free sub-pM detection of DNA and the HAB toxins, microcystin and domoic acid. Finally, we discuss the integration of our metasurfaces with the Environmental Sample Processor developed at MBARI, offering a route to in situ phytoplankton and phytotoxin detection, processing, and analysis.

Presentation Preference: Oral

Primary Presenter: Halleh Balch, Stanford University (balch@stanford.edu)

Authors:

Halleh Balch, Stanford  (balch@stanford.edu)

Varun Dolia, Stanford  (vdolia@stanford.edu)

Sahil Dagli, Stanford  (daglis@stanford.edu)

Jack Hu, Pumpkinseed Technologies  (hujack@stanford.edu)

Darrell Omo-Lamai, Stanford  (deolamai@stanford.edu)

Greg Doucette, NCCOS / NOAA  (greg.doucette@noaa.gov)

William Ussler, MBARI  (methane@mbari.org)

Chris Scholin, MBARI  (scholin@mbari.org)

Jennifer Dionne, Stanford  (jdionne@stanofrd.edu)