High-speed label-free confocal microscopy of Caenorhabditis elegans with near infrared spectrally encoded confocal microscopy

Sadaf Rashtchian; Khaled Youssef; Pouya Rezai; Nima Tabatabaei

doi:10.1364/BOE.427685

High-speed label-free confocal microscopy of Caenorhabditis elegans with near infrared spectrally encoded confocal microscopy

Biomed Opt Express. 2021 May 25;12(6):3607-3618. doi: 10.1364/BOE.427685. eCollection 2021 Jun 1.

Authors

Sadaf Rashtchian¹, Khaled Youssef¹, Pouya Rezai¹, Nima Tabatabaei¹

Affiliation

¹ Mechanical Engineering Department, Lassonde School of Engineering, York University, Toronto, Canada.

Abstract

Caenorhabditis elegans (C. elegans) is an optically transparent nematode that shares many gene orthologs and homologs with humans. C. elegans are widely used in large populations for genetic studies relevant to human biology and disease. Success of such studies frequently relies on the ability to image C. elegans structure at high-resolution and high-speed. In this manuscript, we report on the feasibility and suitability of a high-speed variant of reflectance confocal microscopy, known as spectrally encoded confocal microscopy (SECM), for label-free imaging of C. elegans. The developed system utilizes near-infrared illumination in conjunction with refractive and diffractive optics to instantaneously image a confocal image line at a speed of up to 147 kHz with lateral and axial resolutions of 2µm and 10µm, respectively. Our imaging results from wild-type C. elegans and four mutant strains (MT2124, MT1082, CB61, and CB648) demonstrate the ability of SECM in revealing the overall geometry, key internal organs, and mutation-induced structural variations, opening the door for downstream integration of SECM in microfluidic platforms for high throughput structural imaging of C. elegans.