Analytical Instrumentation Development and Improvements

Development of high-throughput axial MALDI TOF MS instrumentation.

Our laboratory possesses a home-built high-performance MALDI TOF mass spectrometer. The instrument was originally built at Barnett Institute/Northeastern University in Boston. In 2009, it was donated to Masaryk University. It is equipped with a 5 kHz, 355 nm diode-pumped frequency-tripled Nd:YAG laser, fast motorized linear stages moving the MALDI target with speeds up to 5 mm/s and a high-speed 2 GS/s digitizer/averager for data acquisition.

5 kHz MALDI TOF MS "Drobeček"
A unique feature of the instrument is a fast optical scanning system capable of redirecting the desorption laser beam across the MALDI target in sub-millisecond scale. These features make the instrument particularly suitable for high-throughput mass spectrometry imaging – the mapping of the surfaces on molecular level, most commonly focused on analysis of biological tissues (molecular histology). Our instrument is able to generate MS images at least one order of magnitude faster compared to common commercial instruments with kHz lasers. A 10,000 pixel MS image can be acquired in about 1 minute.

Commercial instrumentation

Besides home-built instrumentation, we rely on a commercial MALDI TOF mass spectrometer. We can also easily access two departmental LC-MS systems in our lab, TOF mass spectrometer and hybrid quadrupole-orbitrap mass spectrometer. Both of them are equipped with ESI and IPCI ionization, the latter also with an interface for subatmospheric MALDI.

MALDI TOF MS (Autoflex speed, Bruker)
LC-ESI/APCI/MALDI Q-Orbitrap MS (Ultimate 3000 and Q Exactive Plus, Thermo Scientific).
Shown with the subatmospheric MALDI interface (SubAP/MALDI(ng)UHR, MassTech)
LC-ESI/APCI TOF MS (1200 Series and 6244 TOF LC/MS, Agilent)

Capillary electrophoresis with laser-induced fluorescence

Capillary Electrophoresis presents a modern, high-performance separation method. The separation is based on different migration of analytes in a capillary across which high voltage is applied.
There are three home-built capillary electrophoresis systems in our laboratory. Two of them employ laser-induced fluorescence detection and the last one UV/Vis absorbance detector. Laser-induced fluorescence (LIF) is highly sensitive detection mode and compatible to capillary electrophoresis. It benefits from the superior properties of laser light; especially the directional characteristics and monochromaticity of the laser beam. Thus, both spectral and spatial filtration may be applied to separate fluorescence from the excitation light and achieve sub-attomole detection limits.

Capillary electrophoresis with laser-induced fluorescence

Die Instrumente

Arguably the most favorite apparatus in our group.

What am I used for?

References

Bednařík, A.; Kuba, P; Moskovets, E; Tomalová, I.; Krásenský, P,: Houška, P.; Preisler, J.: “Rapid MALDI TOF Mass Spectrometry Imaging with Scanning Desorption Laser Beam“, Anal. Chem., 2014, 86, 982–986. http://dx.doi.org/10.1021/ac402823n

Moskovets, E.; Preisler, J; Chen, H. S.; Rejtar, T; Andreev, V. Karger. B. L. “High-Throughput Axial MALDI-TOF MS Using a 2 kHz Repetition Rate Laser” Anal. Chem. 2006, 78, 912-919. http://dx.doi.org/10.1021/ac051393t

Ryvolová, M.; Preisler, J.; Krásenský, P.; Foret, F.; Hauser, P.C.; Paull, B.; Macka, M. “Combined Contactless Conductometric, Photometric, and Fluorimetric Single Point Detector for Capillary Separation Methods”, Anal. Chem. 2010, 82, 129-135. http://dx.doi.org/10.1021/ac902376v

Ryvolová, M; Táborský, P; Vrábel, P; Krásenský, P.; Preisler, J. “Sensitive determination of erythrosine and other red food colorants using capillary electrophoresis with laser induced fluorescence detection”, J. Chromatogr. A 2007, 1141, 206-211.

Vrábel, P; Táborský, P; Ryvolová, M; Havel, J.; Preisler, J. “Sensitive Detection and Separation of Fluorescent Derivatives using Capillary Electrophoresis with Laser-Induced Fluorescence Detection with 532 nm Nd:YAG Laser”, J. Lumin. 2006, 118, 283-292.