Multi-color flow cytometer with PIC-based structured illumination

Abstract

We demonstrate a flow cytometer in which structured light illumination is used to attribute fluorescent and scattering signals to their excitation wavelength. A suitable multi-color light source emitting structured illumination patterns at 405, 488, 561 and 640 nm is developed based on a silicon nitride photonic integrated circuit and cytometry experiments are conducted with calibration beads. Performance metrics of the novel cytometer are compared with those of a mature, commercial device. While the experimental device still features a slightly higher sensitivity floor than the commercial one, all but the most weakly stained beads can be categorized. These promising results validate the feasibility of the proposed concept.

On-chip flow cytometer using integrated photonics for the detection of human leukocytes

“…Silicon nitride furthermore allows operation in the visible range with low auto-fluorescence, while showing promise to incorporate light sources, detectors, and other active devices in the near future 19,20 . Photonics on-chip has also been demonstrated to allow the illumination of particles with tailored beam shapes [21][22][23] , but the feasibility of collecting scattered light using integrated waveguides has not yet been studied. In principle, integrated waveguides cannot compete with bulk optics (high NA lenses) or even multimode fibers in terms of collection efficiency due to the small waveguide cross-section.…”

Artificial intelligence in imaging flow cytometry

“…In an IFC system, the specimen flows in a capillary and images of the specimen are rapidly captured by a detector ( Figure 1 ). Illumination of the sample is provided by light emitting diodes (LED) or lasers (not shown in the figure) in different configurations, which include transillumination ( Basiji et al, 2007 ), excitation from an angle ( Goktas et al, 2019 ), structured ( Mashayekh et al, 2022 ) or light-sheet illumination ( Gualda et al, 2017 ). The samples flow in a simple straight tube, in more sophisticated capillaries, or in lab-on-chip devices ( Paiè et al, 2018 ).…”