Trace determination of gadolinium in biomedical samples by diode laser-based multi-step resonance ionization mass spectrometry.

摘要: The application of high-resolution multi-step resonance ionization mass spectrometry (RIMS) to the trace determination rare earth element gadolinium is described. Utilizing three-step resonant excitation into an autoionizing level, both isobaric and isotopic selectivity >107 were attained. An overall detection efficiency ~10–7 isotope specific limit 1.5×109 atoms have been demonstrated. When targeting major 158Gd, this corresponds a total Gd 1.6 pg. Additionally, linear response has demonstrated over dynamic range six orders magnitude. method used determine content in various normal tumor tissue samples, taken from laboratory mouse shortly after injection diethylenetriaminepentaacetic acid dimeglumine (Gd-DTPA), which as contrast agent for magnetic imaging (MRI). RIMS results show concentrations that vary by more than two magnitude (0.07–11.5 µg mL–1) depending on type. This variability similar observed MRI scans depict Gd-DTPA prior dissection, illustrates potential quantitative analysis microsamples biomedical materials.