Open AccessBiophysical investigation of living monocytes in flow by collaborative coherent imaging techniques
Author(s) -
David Dannhauser,
Domenico Rossi,
Pasquale Memmolo,
Andrea Fińizio,
Pietro Ferraro,
Paolo A. Netti,
Filippo Causa
Publication year - 2018
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.9.005194
Subject(s) - microfluidics , phase imaging , refractive index , cytoplasm , materials science , optical tweezers , light scattering , refractometry , flow (mathematics) , flow cytometry , digital holographic microscopy , digital holography , characterization (materials science) , optics , biological system , microscopy , biophysics , biomedical engineering , scattering , holography , nanotechnology , chemistry , physics , optoelectronics , biology , biochemistry , mechanics , genetics , medicine
We implemented a completely label-free biophysical (morphometric and optical) property characterization of living monocytes in flow, using measurements obtained from two coherent imaging techniques: a pure light scattering approach to obtain an optical signature (OS) of cells, and a digital holography (DH) approach to achieve optical cell reconstructions in flow. A precise 3D cell alignment platform, taking advantage of viscoelastic fluid properties and microfluidic channel geometry, was used to investigate the OS of cells to achieve their refractive index, ratio of the nucleus over cytoplasm, and overall cell dimension. Further quantitative phase-contrast reconstructions by DH were employed to calculate surface area, dry mass, and biovolume of monocytes by using the OS outcomes as input parameters. The results show significantly different biophysical cell properties, confirming the possibility to differentiate monocytes from other cell classes in flow, thus avoiding chemical cell staining or labeling, which are nowadays used.