-
[show abstract]
[hide abstract]
ABSTRACT: Laser ablation (LA) ICP-MS has been developed as a new tool for imaging of cancer biomarkers in tissue sections. The distribution of two breast cancer-associated proteins, MUC-1 and HER2 was studied based on multiple line rastering of tissue sections and measurement of relevant Au/Ag tagged antibodies bound to the tissue. Comparisons with optical microscopy indicated extremely high sensitivity for the LA technique and sufficiently good resolution to permit fine scale feature mapping at the cellular level. Application to the quantitative assessment of HER2 expression in tissue microarrays was demonstrated.
Proteomics 09/2008; 8(18):3775-84. · 4.43 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The 234U/238U isotope ratio has been widely used as a tracer for geochemical processes in underground aquifers. Quadrupole-based inductively coupled plasma mass spectrometry (ICP-MS) equipped with a high-efficiency nebulizer and a membrane desolvator was employed for the determination of 234U/238U isotope ratios in natural water samples. The instrumental limit of detection for 234U was at the low pg L(-1) level with very low sample consumption. Measurement precision (234U/238U) was 3-5% for bottled mineral water with elevated uranium concentration (>1 microg L(-1)). For the analysis of groundwater samples from the Almonte-Marisma underground aquifer (Huelva, Spain), uranium was stripped from stainless steel planchets that had previously been used as radiometric counting sources for alpha-particle spectrometry. Potential spectral interferences from other metals introduced during the dissolution were investigated. Matrix-matched blank solutions were needed to subtract the background on 234U due to the formation of platinum argides, and to allow for mass bias correction and background correction. The Pt appears to be an impurity present in the stainless steel, either as a minor component by itself or after extraction from the anode and a subsequent uranium electrodeposition. The 234U/238U isotope ratio data were in very good agreement with those of alpha spectrometry, while precision was improved by a factor of up to 10 and counting time was reduced down to approximately 20 min (10 replicate measurements).
Analytical and Bioanalytical Chemistry 09/2006; 386(1):152-60. · 3.78 Impact Factor
-
Kidney International 01/2006; 68(6):2906; author reply 2906-7. · 6.61 Impact Factor
