Femtosecond laser-induced X-ray fluorescence measurement of metal-protein compounds

Abstract

We measured the metal-protein compounds X-ray fluorescence by the laser-induced X-ray source with an aluminum tape target. The laser-induced X-ray generated by the high repetition rate (1 kHz) femtosecond (40 fs) Ti: Sapphire laser system. To characterize a laser-induced K alpha and bremsstrahlung X-ray source, we changed the laser intensity and pulse focused position. We measured the X-ray fluorescence signal with the copper plate, selenium powder, lyophilized hemoglobin, and lyophilized seleno-methionine, which was detected by X-ray spectrometer. With a few micrograms of samples, the X-ray fluorescence can be measured with high accuracy and high stability.