Filtern
Erscheinungsjahr
Dokumenttyp
- Zeitschriftenartikel (91)
- Vortrag (68)
- Sonstiges (9)
- Buchkapitel (4)
- Posterpräsentation (4)
- Beitrag zu einem Sammelband (1)
Schlagworte
- ICP-MS (30)
- Laser ablation (16)
- Nanoparticles (15)
- LA-ICP-MS (14)
- Cell (11)
- Nanoparticle (8)
- Bioimaging (7)
- Speciation (7)
- Imaging (6)
- Mass cytometry (5)
Organisationseinheit der BAM
Eingeladener Vortrag
- nein (68)
Elementmassenspektrometrie und Metallomics als neue Herausforderung für die Lebenswissenschaften
(2009)
An immunoassay was developed for ochratoxin A (OTA) detection in wine and two completely different detection methods were compared: ICP-MS and photometry. For labelling, we applied secondary antibodies conjugated with gold nanoparticles for ICP-MS and with horseradish peroxidase for photometric detection, respectively. Detection limits of the assay were determined as 0.003 µg L-1 for both detection methods. OTA in wine was determined below the EU limit value of 2 µg kg-1. The measurement range was between 0.01 and 1 µg L-1 for ICP-MS and photometric detection. Assay precision detected by ICP-MS and photometry were similar showing that precision of the detection method has only a minor effect on total assay precision. By using BSA as a buffer additive to minimize nonspecific binding, we could also confirm that OTA strongly binds to BSA. In a comparison study of several additives, casein was found to be preferable.
For the study of bladder cancer and the identification of respective tumor markers, blood and, in particular, urine constitute suitable sources of biological material, while both harboring their specific challenges for analytics concerning low-abundance biomarkers. Dissolved proteins and nucleic acids as well as cells and cell-bound molecules can be the analytes. In urine, exfoliated bladder tumor cells have to be identified and in blood, circulating tumor cells have to be detected among huge amounts of other cells. For the detection of both low-abundance cells and molecules, their specific enrichment prior to analysis is advantageous or even necessary. Adapted methods for the analysis of proteomes and subproteomes by 2D-gel electrophoresis, multidimensional chromatography and antibody arrays are discussed. Analysis of nucleic acid-based markers exploits the high amplification power of PCR and modified PCR combined with previous (subtransciptomes) or subsequent (microarray) enrichment to sensitively and specifically detect markers. DNA mutations, DNA-methylation status and apoptotic DNA fragments, as well as levels of ribonucleic acids including microRNAs, can be analyzed by means of these methods. Finally, the challenge of identifying circulating tumor cells and assigning them to their original tissue is critically discussed.
Analytische Chemie 2008/2009
(2010)