An integrated centrifugal microfluidic strategy for point-of-care complete blood counting

Centrifugal microfluidics holds the potential to revolutionize point-of-care (POC) testing by simplifying laboratory tests through automating fluid and cell manipulation within microfluidic channels. This technology can facilitate blood testing, the most frequent clinical test, at the POC. However, an integrated centrifugal microfluidic device for complete blood counting (CBC) has not yet been fully realized. To address this, we propose an integrated portable system comprising a centrifuge and a hybrid microfluidic disc specifically designed for CBC analysis at the POC. The disc enables the implementation of various spin profiles in different stages of CBC to facilitate in-situ cell separation, solution metering and mixing, and differential cell counting. Furthermore, our system is coupled with a custom script that automates the process and ensures precise quantification of cells using light and fluorescent images captured from the detection chamber of the disc. We demonstrate a close correlation between the proposed method and the hematology analyzer, considered the gold standard, for quantifying hematocrit (R-2 = 0.99), white blood cell count (R-2 = 0.98), white blood cell differential count (granulocyte/agranulocyte; R-2 = 0.89), red blood cell count (R-2 = 0.97), and mean corpuscular volume (R-2 = 0.94). The integration of our portable system offers significant advantages, enabling more accessible and affordable CBC testing at the POC. Considering the simplicity, affordability (similar to$250 capital cost and <$2 operational cost per test), as well as low power consumption (>100 tests using a typical 24 V/10 Ah battery), this system has the potential to enhance healthcare delivery, particularly in resource-limited settings and remote areas where access to traditional laboratory facilities is limited.

Automated summary

This paper introduces an integrated portable centrifugal microfluidic system that automates cell and fluid manipulation for complete blood counting (CBC) analysis at the point-of-care (POC). The system utilizes a specially designed microfluidic disc for cell separation, solution metering and mixing, and cell counting, and is equipped with a custom script for automated quantification of cells. The proposed method shows a strong correlation with the gold standard hematology analyzer for various blood parameters. The portable system offers simplicity, affordability, and low power consumption, making it a potential solution for improving healthcare delivery in resource-limited settings and remote areas.