Spectroscopic phase microscopy for quantifying hemoglobin concentrations in intact red blood cells

Abstract

We report a practical method for label-free quantification of specific molecules using spectroscopic imaging of sampleinduced phase shifts (for the detail, please see the Ref. [1]). Diffraction phase microscopy equipped with various wavelengths of light source is used to record wavelength-dependent phase images. We first perform dispersion measurements on pure solutions of single molecular species present in the cells, such as albumin and hemoglobin (Hb). With this prior calibration of molecular specific dispersion, we demonstrate the extraction of Hb concentration from individual red blood cells (RBCs). The end point of this study is non-invasive monitoring of physiological states of intact living cells.