Reduce complexity and increase signal-to-noise ratio
Flow cytometers analyze multiple properties of cells rapidly flowing through a fluidic system. Cells are colored with bright fluorescent dyes to label specific structures of interest or to increase the contrast.
Most flow cytometers use photomultiplier tubes (PMTs) as detectors. Up to four (4) detectors are used for forward and side scattering detection and up to sixty-four (64) fluorescence detectors.
PMTs are mature detectors with high dynamic range and large active area. However, they are typically implemented as single point detectors, thus a flow cytometer exhibits a large number of detectors. Additionally, PMTs have limited sensitivity below 45% quantum efficiency and excess noise when used in analog mode, both contributing to lowering the signal-to-noise ratio.
SPAD arrays offer a large number of integrated pixels, providing the capability to combine all fluorescence detectors into one, reducing integration complexity and cost. Additionally, SPADs are optimized for high sensitivity and offer Poisson-limited signal-to-noise ratio.
Benefits of SPAD technology
for this application
Enhanced sensitivity
SPAD arrays are optimized for a wide detection spectrum and offer higher sensitivity than photomultiplier tubes (PMT).
Improved signal-to-noise ratio
The single-photon counting nature of SPADs results in lower noise levels compared to analog PMT detectors.
Compact spectral detection
SPAD detectors have high pixel numbers, allowing to replace multiple PMTs with one SPAD detector.
Recommended products
SPAD Lambda
SPAD Lambda is the ideal solution for a spectroscopy setup. Benefiting from the linear 320, individually time-tagged pixels and in-pixel gated electronics, SPAD Lambda offers flexibility and high timing precision for any spectroscopy application.
References
Tsoukias, Stefanos, et al.
BIOS 12849-35. SPIE (2024).
Ma, Yayao, et al.
PNAS (2024). https://doi.org/10.1073/pnas.2402556121.
