Quantitative phase imaging of erythrocytes under microfluidic constriction in a high refractive index medium reveals water content changes

• Authors: Han Sang Park, Duke University; Will J. Eldridge, Duke University; Wen-Hsuan Yang, Duke University; Michael Crose, Duke University; Silvia Ceballos, Duke University; John Roback, Emory University; Jen-Tsan Alshey Chi, Duke University; Adam Wax, Duke University
• Journal Title: Microsystems and Nanoengineering
• Volume: Volume 5, Number 1
• Publisher: Nature Publishing Group | 2019-12-02, Pages 63-63
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1038/s41378-019-0113-y
• Subjects: Engineering, Biomedical
• Keywords: Science & Technology; Technology; Nanoscience & Nanotechnology; Instruments & Instrumentation; Science & Technology - Other Topics; RED-BLOOD-CELLS; STORAGE; DEFORMABILITY; RETICULOCYTE

Abstract

Changes in the deformability of red blood cells can reveal a range of pathologies. For example, cells which have been stored for transfusion are known to exhibit progressively impaired deformability. Thus, this aspect of red blood cells has been characterized previously using a range of techniques. In this paper, we show a novel approach for examining the biophysical response of the cells with quantitative phase imaging. Specifically, optical volume changes are observed as the cells transit restrictive channels of a microfluidic chip in a high refractive index medium. The optical volume changes indicate an increase of cell’s internal density, ostensibly due to water displacement. Here, we characterize these changes over time for red blood cells from two subjects. By storage day 29, a significant decrease in the magnitude of optical volume change in response to mechanical stress was witnessed. The exchange of water with the environment due to mechanical stress is seen to modulate with storage time, suggesting a potential means for studying cell storage.