抄録
We have investigated the secondary ion emission from arginine amino acid thin films under fast heavy ion irradiation using the time-of-flight technique. In a previous study, we reported on the high yield of arginine ions and low relative intensities of fragment ions compared to 10 keV Ar+ irradiation. These features would be useful for identification of biological mixtures. In this work, we measured secondary ion yields from mixed samples of the drug ipratropium bromide (IB) and cholesterol at various concentrations under 6 MeV Cu4+ irradiation. We detected molecular-related ions of IB from mixture films composed of a molar ratio of 0.33% IB to cholesterol at high sensitivity. The yield ratios of IB ions to cholesterol ions showed linear dependence on the molar concentration ratios of IB to cholesterol. These results indicate that secondary ion mass spectrometry (SIMS) using high-energy ions is useful for quantitative microanalysis of drugs in real biological samples.
