Microlaser spectroscopy for quantifying anemia by intracellular blood hemoglobin measurements

Summary form only given. The authors present a new analysis of single-cell hemoglobin using a microcavity laser. Such microlaser techniques have the potential to be rapid, inexpensive alternatives to conventional hematologic methods that require expensive instruments. The method determines the concentration of hemoglobin and its variation among red blood cells using only 10 pl of whole blood diluted in saline. A schematic shows the cells in the microcavity. Two different red cell optical modes and corresponding stimulated emission spectra are shown. The spontaneous emission spectra are recorded with and without the cell present, respectively. A dominant peak at 840 nm corresponds to the longitudinal mode of the cavity containing only the blood plasma. With the cell present, a series of spectral peaks occurs on the long wavelength side of the longitudinal mode. These peaks correspond to transverse optical modes confined by the red blood cell. The rightmost peak in this series is the fundamental.