TY - JOUR A1 - Müller, Larissa A1 - Jakubowski, Norbert A1 - Hösl, Simone A1 - Scheler, C. A1 - Roos, P.H. A1 - Linscheid, M.W. T1 - Comparison of different chelates for lanthanide labeling of antibodies and application in a Western blot immunoassay combined with detection by laser ablation (LA-)ICP-MS JF - Journal of analytical atomic spectrometry N2 - We have developed lanthanide labeling strategies for antibodies to adapt conventional biochemical workflows like Western blot immunoassays for detection by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis with a special interest to apply the multi-element capabilities of ICP-MS for the design of multiplexed immunoassays. In this paper the lanthanide labeling of antibodies with MeCAT was investigated and the reaction conditions were optimized for application in a Western blot immunoassay analyzed by LA-ICP-MS. Furthermore, the MeCAT labeling strategy was compared with two other commercially available labeling reagents, MAXPAR™ and SCN-DOTA. As a proof-of-principle experiment chemically induced alterations of cytochrome P450 protein expression were investigated and the suitability of the differentially labeled antibodies for Western blot immunoassays of a complex liver microsomal protein fraction was tested. Limits of detection (LODs) in the lower fmol range were reached in the Western blot application using MeCAT and MAXPAR™ as element labeling reagents, whereas even sub-fmol LODs can be achieved in a dot blot experiment for the pure antibodies. PY - 2012 DO - https://doi.org/10.1039/c2ja30068k SN - 0267-9477 SN - 1364-5544 N1 - Geburtsname von Müller, Larissa: Wäntig, L. - Birth name of Müller, Larissa: Wäntig, L. N1 - Geburtsname von Hösl, Simone: Hardt, S. - Birth name of Hösl, Simone: Hardt, S. VL - 27 IS - 8 SP - 1311 EP - 1320 PB - Royal Society of Chemistry CY - London AN - OPUS4-26256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Moreno-Gordaliza, E. A1 - Esteban-Fernández, D. A1 - Giesen, Charlotte A1 - Lehmann, K. A1 - Lázaro, A. A1 - Tejedor, A. A1 - Scheler, C. A1 - Canas, B. A1 - Jakubowski, Norbert A1 - Linscheid, M.W. A1 - Gómez-Gómez, M.M. T1 - LA-ICP-MS and nHPLC-ESI-LTQ-FT-MS/MS for the analysis of cisplatin-protein complexes separated by two dimensional gle elctrophoresis in biological samples JF - Journal of analytical atomic spectrometry N2 - A method for the analysis of Pt–protein complexes in biological samples, previously subjected to cisplatin treatment, has been developed. Proteins were separated by gel electrophoresis, and those bound to Pt were detected with high sensitivity by LA-ICP-(SF)-MS. Pt-containing spots were in-gel digested with trypsin, and the peptides produced identified using nHPLC-ESI-LTQ-FT-MS/MS. The influence of protein separation conditions, staining and gel processing prior to laser ablation on Pt–protein bonds preservation have been evaluated using standard proteins incubated with cisplatin. 2-DE separation under non-reducing conditions followed by either Coomassie blue brilliant or silver staining is appropriate for Pt–protein complexes, achieving a good separating resolution of the proteins in biological samples. Direct LA-ICP-MS analysis of glycerol-treated dried gels for Pt–protein monitoring resulted in better sensitivity, more reliable relative Pt signals and a simpler and less time-consuming approach compared to the analysis of blotted membranes. Ablation of gels allowed tackling protein identification of Pt-spots in the remaining non-ablated material in the gel, making it unnecessary to run several gels in parallel for separate Pt detection and protein identification. By using this approach, Pt coordinated to proteins, such as α-2-macroglobulin, transferrin, albumin or hemoglobin, was detected in the serum from a rat treated in vivo with cisplatin after nrSDS-PAGE separation. Furthermore, the first complete LA-ICP-MS metalloprotein contour map in a 2-DE gel has been produced, in this case for the detection of Pt–protein complexes in renal proximal tubule epithelial cells (RPTECs) incubated with cisplatin. Several proteins were identified in those spots containing Pt, which may have a connection with the drug-induced nephrotoxicity mainly affecting this cell type in the kidney. PY - 2012 DO - https://doi.org/10.1039/c2ja30016h SN - 0267-9477 SN - 1364-5544 VL - 27 IS - 9 SP - 1474 EP - 1483 PB - Royal Society of Chemistry CY - London AN - OPUS4-26562 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Giesen, C. A1 - Müller, Larissa A1 - Panne, Ulrich A1 - Jakubowski, Norbert T1 - History of inductively coupled plasma mass spectrometry-based immunoassays JF - Spectrochimica acta B N2 - The analysis of biomolecules requires highly sensitive and selective detection methods capable of tolerating a complex, biological matrix. First applications of biomolecule detection by ICP-MS relied on the use of heteroelements as a label for quantification. However, the combination of immunoassays and ICP-MS facilitates multiparametric analyses through elemental tagging, and provides a powerful alternative to common bioanalytical methods. This approach extends the detection of biomarkers in clinical diagnosis, and has the potential to provide a deeper understanding of the investigated biological system. The results might lead to the detection of diseases at an early stage, or guide treatment plans. Immunoassays are well accepted and established for diagnostic purposes, albeit ICP-MS is scarcely applied for the detection of immune-based assays. However, the screening of biomarkers demands high throughput and multiplex/multiparametric techniques, considering the variety of analytes to be queried. Finally, quantitative information on the expression level of biomarkers is highly desirable to identify abnormalities in a given organism. Thus, it is the aim of this review to introduce the fundamentals, and to discuss the enormous strength of ICP-MS for the detection of different immunoassays on the basis of selected applications, with a special focus on LA-ICP-MS. KW - ICP-MS KW - LA-ICP-MS KW - Immunoassay KW - Elemental tagging KW - Multiplexing PY - 2012 DO - https://doi.org/10.1016/j.sab.2012.06.009 SN - 0584-8547 SN - 0038-6987 N1 - Geburtsname von Müller, Larissa: Wäntig, L. - Birth name of Müller, Larissa: Wäntig, L. VL - 76 SP - 27 EP - 39 PB - Elsevier CY - Amsterdam AN - OPUS4-27686 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drescher, Daniela A1 - Giesen, Charlotte A1 - Traub, Heike A1 - Panne, Ulrich A1 - Kneipp, Janina A1 - Jakubowski, Norbert T1 - Quantitative imaging of gold and silver nanoparticles in single eukaryotic cells by laser ablation ICP-MS JF - Analytical chemistry N2 - Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was utilized for spatially resolved bioimaging of the distribution of silver and gold nanoparticles in individual fibroblast cells upon different incubation experiments. High spatial resolution was achieved by optimization of scan speed, ablation frequency, and laser energy. Nanoparticles are visualized with respect to cellular substructures and are found to accumulate in the perinuclear region with increasing incubation time. On the basis of matrix-matched calibration, we developed a method for quantification of the number of metal nanoparticles at the single-cell level. The results provide insight into nanoparticle/cell interactions and have implications for the development of analytical methods in tissue diagnostics and therapeutics. KW - Imaging KW - Cell KW - Nanoparticles KW - Laser ablation KW - ICP-MS PY - 2012 DO - https://doi.org/10.1021/ac302639c SN - 0003-2700 SN - 1520-6882 VL - 84 IS - 22 SP - 9684 EP - 9688 PB - American Chemical Society CY - Washington, DC AN - OPUS4-27440 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -