本文首次报道了血红蛋白吸收二个和四个1.06μm的光子后所发射的荧光特性,并分析了其产生的原因。

Hemoglobin and other samples were irradiated by the 1064 nm light of a nanosecond pulse Nd:YAG laser. At room temperature, we first observed two red fluorescence bands which result from absorbing two 1064 nm photons in hemoglobin (Hb), and we measured the fluorescence emission spectra at red region for Hb and hemotoporphyrin derivative (HpD). Both Hb and HpD have two fluorescence emission maxima. A red shift in wavelength and a mirror image in the intensity of fluorscence emissions by two-photon excitation relative to that by one-photon (532-nm) excitation were observed. The experimental analysis showed that the fluorescence of Hb originates from the porphyrin ring of the heme group, just as that of HpD from the porphyrin ring. Besides, we also observed the fluorescence emission at UY 392-nm for Hb, which may come from the tryptophans in Hb.