A photonic resonator interferometric scattering microscope for label-free detection of nanoparticles in point-of-use environments

Label-free detection and digital counting of nanometer-scaled objects such as nanoparticles, viruses, extracellular vesicles, and protein molecules enable a wide range of applications in cancer diagnostics, pathogen detection, and life science research. This thesis concludes the design, implementation, and characterization of a compact Photonic Resonator Interferometric Scattering Microscope designed for point-of-use environments and applications. The contrast of interferometric scattering microscopy is amplified through a photonic crystal surface, upon which scattered light from an object combines with illumination from a monochromatic source. The use of a photonic crystal substrate for interferometric scattering microscopy results in reduced requirements for high-intensity lasers or oil-immersion objectives, thus opening a pathway toward instruments that are more suitable for environments outside the optics laboratory. The instrument incorporates two innovative elements that facilitate operation on a desktop in ordinary laboratory environments by users that do not have optics expertise. First, due to extreme sensitivity to vibration, the imaging system is incorporated with an inexpensive but effective solution of suspending the instrument’s main components from a rigid metal framework using elastic bands, resulting in an average of 28.7 dBV reduction in vibration amplitude compared to an office desk. Second, an autofocusing module maintains the stability of image contrast over time and spatial position. The system's performance is characterized by measuring the contrast from gold nanoparticles with diameters in the 10-40 nm range and by observing various biological analytes, including human immunodeficiency virus, severe acute respiratory syndrome coronavirus 2, exosomes, and ferritin protein.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Electrical & Computer Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2023

Author dc:creator

• Liu, Leyang

Contributors dc:contributor

• Cunningham, Brian T.

• Iscat
• Label-free
• Nanoparticles
• Photonic Crystals

Statement dc:rights

• Copyright 2023 Leyang Liu

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/120253

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F120253