Smart palm-size optofluidic hematology analyzer for automated imaging-based leukocyte concentration detection

A critical function of flow cytometry is to count the concentration of blood cells, which helps in the diagnosis of certain diseases. However, the bulky nature of commercial flow cytometers makes such tests only available in hospitals or laboratories, hindering the spread of point-of-care testing (POCT), especially in underdeveloped areas. Here, we propose a smart Palm-size Optofluidic Hematology Analyzer based on a miniature fluorescence microscope and a microfluidic platform to lighten the device to improve its portability. This gadget has a dimension of 35 × 30 × 80 mm and a mass of 39 g, less than 5% of the weight of commercially available flow cytometers. Additionally, automatic leukocyte concentration detection has been realized through the integration of image processing and leukocyte counting algorithms. We compared the leukocyte concentration measurement between our approach and a hemocytometer using the Passing-Bablok analysis and achieved a correlation coefficient of 0.979. Through Bland-Altman analysis, we obtained the relationship between their differences and mean measurement values and established 95% limits of agreement, ranging from -0.93×10³ to 0.94×10³ cells/μL. We anticipate that this device can be used widely for monitoring and treating diseases such as HIV and tumors beyond hospitals.