Open AccessNanometer precise red blood cell sizing using a cost-effective quantitative dark field imaging system
Author(s) -
Xiaoya Chen,
Peng Luo,
Chuanzhen Hu,
Shaojie Yan,
Dapeng Lu,
Yaning Li,
Kaiqin Chu,
Zachary J. Smith
Publication year - 2020
Publication title -
biomedical optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.362
H-Index - 86
ISSN - 2156-7085
DOI - 10.1364/boe.405510
Subject(s) - mie scattering , mean corpuscular hemoglobin , optics , mean corpuscular volume , scattering , dark field microscopy , calibration , computer science , light scattering , microscope , materials science , physics , microscopy , hemoglobin , medicine , quantum mechanics
Because of the bulk, complexity, calibration requirements, and need for operator training, most current flow-based blood counting devices are not appropriate for field use. Standard imaging methods could be much more compact, inexpensive, and with minimal calibration requirements. However, due to the diffraction limit, imaging lacks the nanometer precision required to measure red blood cell volumes. To address this challenge, we utilize Mie scattering, which can measure nanometer-scale morphological information from cells, in a dark-field imaging geometry. The approach consists of a custom-built dark-field scattering microscope with symmetrically oblique illumination at a precisely defined angle to record wide-field images of diluted and sphered blood samples. Scattering intensities of each cell under three wavelengths are obtained by segmenting images via digital image processing. These scattering intensities are then used to determine size and hemoglobin information via Mie theory and machine learning. Validation on 90 clinical blood samples confirmed the ability to obtain mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and red cell distribution width (RDW) with high accuracy. Simulations based on historical data suggest that an instrument with the accuracy achieved in this study could be used for widespread anemia screening.