Thursday, 13 January 2011
Sulphur detection in proteins
The analytical spectrometry research group at the University of Oviedo in Asturias, Spain, aims to solve the analytical challenges encountered by science and technology. Within this framework, a small sub-group has been established focusing on the development of inductively coupled plasma-mass spectrometry (ICP-MS) based analytical methods for the quantification of biopolymers such as DNA and proteins. One of the principal issues faced by the group is the interference from gas-based polyatomics such as oxygen in the determination of sulphur when using a low resolution instrument. To eliminate these problems, the group selected the Thermo Scientific XSERIES 2 ICP-MS with collision/reaction cell technology (CRC).
Quantitative protein analysis is currently one of the most demanding applications in analytical chemistry. Mass spectrometric techniques such as electrospray ionization-mass spectrometry (ESI-MS) and matrix assisted laser desorption ionization-mass spectrometry (MALDI-MS) have traditionally played a key role in protein analysis. However, the potential of ICP-MS has recently been recognized for the determination of proteins. Although ICP-MS detection does not provide any structural information, its outstanding capability to quantify most of the elements proves valuable for accurate protein quantification. Keeping pace with the latest technological developments, the University of Oviedo's research group has coupled the XSERIES 2 ICP-MS with a reversed-phase capillary liquid chromatography (?LC) system to facilitate precise determination of sulphur isotopes in standard proteins.
Dr Jörg Bettmer of the University of Oviedo's analytical spectrometry research group comments, "The Thermo Scientific XSERIES 2 ICP-MS was chosen because no other quadrupole-based system matches its capabilities in terms of accuracy, reliability and overall efficiency. The implementation of the instrument has allowed us to achieve reliable, interference-free detection of sulphur isotopes. It has enabled us to determine sulphur-containing standard proteins in an accurate and efficient manner that had not been previously possible."
The XSERIES 2 offers outstanding productivity in a quadrupole ICP-MS for both routine and high-performance analytical applications. By using the system, laboratories can achieve their analytical objectives faster, with greater confidence and less hands-on time from the operator. The ion lens design of the instrument enables simple field upgrade to collision cell technology (CCT) performance without affecting the normal (non-CCT mode) sensitivity or background. The cell is also compatible with a range of reactive gases, such as pure oxygen for interference suppression in challenging matrices.