Posters-Accepted Abstracts: J Chromatogr Sep Tech
Nanometer-sized cadmium telluride particles were used as an inorganic matrix for the laser desorption/ionization mass spectrometry of free fatty acids in human serum. By changing the excitation power and the amount of a hole scavenger, the peak of deprotonated fatty acids was investigated. It was understood that the ionization of fatty acids were due to the biexciton Auger recombination and electron ejection from CdTe. CdTe were then loaded on zeolite surface. The peak intensity enhancement of the deprotonated ion of fatty acid was observed. This phenomenon was explained by measuring the carrier lifetime for Auger recombination in CdTe. In addition, reproducibility of fatty acid ions was highly improved reflecting homogeneous distribution of CdTe on zeolite surface. CdTe loaded on a zeolite surface (HM20) was successfully applied to the quantitative analysis of Ste in human serum by isotope dilution using 13C18-Ste. The concentration of Ste in human serum samples was estimated to be 76.62 mg/kg with the standard deviation (SD) of 2.37mg/kg.