Study of sample preparation for biological applications ICP MS
Pavla Foltynová
New approaches of sample introduction to inductively-coupled plasma mass spectrometry
(ICP MS) are presented - substrate-assisted laser (SALD ICP MS) and diode laser thermal
vaporization (DLTV ICP MS). These methods are suitable for quantitative elemental analysis
of low volume samples (typically 100 – 500 nL) with minimal or no sample pretreatment and
represent an alternative to nebulizers.
SALD ICP MS is suitable for off-line coupling with capillary electrophoresis for
speciation analysis and biological samples, such as metalloproteins or metal complexes can be
analyzed also in the different detection modes, such as matrix-assisted laser
desorption/ionization mass spectrometry (MALDI MS) after addition of matrix to the sample.
Complementary SALD ICP MS and MALDI MS techniques provide information on both
metal content and protein mass or identity from the same sample. Applicability of SALD ICP
MS was demonstrated on study of copper metabolism in disulfiram-treated myeloid leukemia
U937 cells and determination of copper in Blue exploding protein of Neocapritermes taracu.
In contrast to laser ablation or SALD ICP MS, the LDTV does not require an expensive
high-energy pulse laser; the technique employs a low-cost NIR diode laser. The diode laser
induces pyrolysis and/or burning of the substrate and the generated aerosol is carried out into
the plasma torch. The technique was applied to determine lead in whole blood and tin in
canned food.
Detailed characterization of both methods and their applications will be discussed.