title: Optical phase nanoscopy in red blood cells using low-coherence spectroscopy.
abstract: We propose a low-coherence spectral-domain phase microscopy (SDPM) system for accurate quantitative phase measurements in red blood cells (RBCs) for the prognosis and monitoring of disease conditions that affect the visco-elastic properties of RBCs. Using the system, we performed time-recordings of cell membrane fluctuations, and compared the nano-scale fluctuation dynamics of healthy and glutaraldehyde-treated RBCs. Glutaraldehyde-treated RBCs possess lower amplitudes of fluctuations, reflecting an increased membrane stiffness. To demonstrate the ability of our system to measure fluctuations of lower amplitudes than those measured by the commonly used holographic phase microscopy techniques, we also constructed wide-field digital interferometry (WFDI) system and compared the performances of both systems. Due to its common-path geometry, the optical-path-delay stability of SDPM was found to be less than 0.3 nm in liquid environment, at least three times better than WFDI under the same conditions. In addition, due to the compactness of SDPM and its inexpensive and robust design, the system possesses a high potential for clinical applications.
authors.affiliation: Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Itay
authors.initials: I
authors.lastname: Shock
authors.forename: Alexander
authors.initials: A
authors.lastname: Barbul
authors.forename: Pinhas
authors.initials: P
authors.lastname: Girshovitz
authors.forename: Uri
authors.initials: U
authors.lastname: Nevo
authors.forename: Rafi
authors.initials: R
authors.lastname: Korenstein
authors.forename: Natan T
authors.initials: NT
authors.lastname: Shaked
mesh_terms: D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects / Q000502:physiology; D004548:Elasticity; D004912:Erythrocytes / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D005976:Glutaral / Q000494:pharmacology; D006801:Humans; D007368:Interferometry; D008853:Microscopy / Q000379:methods*; D036103:Nanotechnology / Q000379:methods*; D041623:Tomography, Optical Coherence / Q000379:methods*; D014783:Viscosity
chemical_list: D005976:Glutaral