# Research on the Method of Detecting TPN-Labeled Tumor Cells in Pleural Effusion Based on the Microfluidic Chip

## TL;DR

This study presents a microfluidic chip method to efficiently detect and isolate tumor cells in pleural effusion using a mitochondrial marker called TPN.

## Contribution

A novel microfluidic chip design is introduced for high-purity tumor cell enrichment and TPN-based detection in pleural effusion.

## Key findings

- The microfluidic chip achieved 98.7–99.3% purity in enriching A549, MCF-7, and Hela tumor cells.
- TPN fluorescent labeling was successfully used to identify tumor cells on the microfluidic chip.
- The chip demonstrated potential for improving clinical diagnosis of malignant pleural effusion.

## Abstract

The clinical diagnosis of a malignant pleural effusion (MPE) is still based on the detection of tumor cells in the pleural effusion. The question of how to improve the efficiency and accuracy of detecting an MPE still remains. This study explores the use of microfluidic technology to concentrate cells in an MPE and achieved the detection of the cell marker TPN in the microarray capture area. TPN is a mitochondria-specific bio-probe that can identify tumor cells on the basis of differences in the mitochondrial potential. First, we designed a microfluidic chip to analyze its performance. The results show that when the total flow rate of the injected chip was 12 mL/h and the volume ratio of cell separation liquid to cell suspension was 1:1, the target cells (A549, MCF-7, and Hela) were enriched and the purity was improved to 98.7–99.3%. Finally, an MPE from cancer patients was used to detect the chip’s ability to isolate and enrich tumor cells. Furthermore, the fluorescent identification of the TPN within the tumor cells was simultaneously achieved on the microfluidic chip. In conclusion, the potential to improve the efficiency of the clinical diagnosis of MPEs is provided by the chip structure and analysis conditions explored in this study.