# A Miniature Modular Fluorescence Flow Cytometry System

## TL;DR

A new modular flow cytometry system allows flexible fluorescence detection and is compact and efficient for cell analysis.

## Contribution

The development of a modular fluorescence flow cytometry system with flexible channel arrangement and high signal-to-noise ratio.

## Key findings

- The M-FCM system achieved a signal-to-noise ratio of 33.2 dB.
- The system successfully evaluated cell viability in drug screening with results matching commercial cytometry.
- The modular design allows for multifunctional measurements like electrical impedance and refractive-index detection.

## Abstract

Fluorescence flow cytometry is a powerful instrument to distinguish cells or particles labelled with high-specificity fluorophores. However, traditional flow cytometry is complex, bulky, and inconvenient for users to adjust fluorescence channels. In this paper, we present a modular fluorescence flow cytometry (M-FCM) system in which fluorescence channels can be flexibly arranged. Modules for particle focusing and fluorescence detection were developed. After hydrodynamical focusing, the cells were measured in the detection modules, which were integrated with in situ illumination and fluorescence detection. The signal-to-noise ratio of the detection reached to 33.2 dB. The crosstalk among the fluorescence channels was eliminated. The M-FCM system was applied to evaluate cell viability in drug screening, agreeing well with the commercial cytometry. The modular cytometry presents several outstanding features: flexibility in setting fluorescence channels, cost efficiency, compact construction, ease of operation, and the potential to upgrade for multifunctional measurements. The modular cytometry provides a multifunctional platform for various biophysical measurements, e.g., electrical impedance and refractive-index detection. The proposed work paves an innovative avenue for the multivariate analysis of cellular characteristics.