Towards Surface Plasmon Resonance biosensing combined with bioaffinity-assisted nano HILIC Liquid Chromatography Time-of-flight Mass Spectrometry identification of Paralytic Shellfish Poisons

The potential for coupling technologies to deliver new, improved forms of bioanalysis is still in its infancy. We review a number of examples in which coupling has been successful, with special emphasis on combining surface-plasmon-resonance biosensors with mass spectrometry. We give an overview of current progress towards combining biosensor-based bioanalysis with chemical analysis for confirmation of paralytic shellfish poisons that are marine toxins. This comprehensive approach could be an alternative to the official methods currently used (e.g., animal testing and high-performance liquid chromatography with fluorescence detection) and could serve as a model for many more such applications. (C) 2009 Elsevier Ltd. All rights reserved.

Time of flight mass spectrometry for quantitative data analysis in fast transient studies using a Temporal Analysis of Products (TAP) reactor

A Time of flight (ToF) mass spectrometer suitable in terms of sensitivity, detector response and time resolution, for application in fast transient Temporal Analysis of Products (TAP) kinetic catalyst characterization is reported. Technical difficulties associated with such application as well as the solutions implemented in terms of adaptations of the ToF apparatus are discussed. The performance of the ToF was validated and the full linearity of the specific detector over the full dynamic range was explored in order to ensure its applicability for the TAP application. The reported TAP-ToF setup is the first system that achieves the high level of sensitivity allowing monitoring of the full 0-200 AMU range simultaneously with sub-millisecond time resolution. In this new setup, the high sensitivity allows the use of low intensity pulses ensuring that transport through the reactor occurs in the Knudsen diffusion regime and that the data can, therefore, be fully analysed using the reported theoretical TAP models and data processing.

Characterisation of polyacetylenes in carrot extracts using electrospray ionisation quadrupole time of flight mass spectrometry.

Rai, D., Koidis, A., Rawson, A., McLouglin, P., Brunton, N. (2010). Characterisation of polyacetylenes in carrot extracts using electrospray ionisation quadrupole time of flight mass spectrometry. Delegate CD-Rom PS2.8, EFFoST Annual Meeting, Dublin, Ireland, 10 -12/11/2010 (Poster).

Identification of an unknown b-agonist in feed by liquid chromatography/bioassay/quadrupole time-of-flight tandem mass spectrometry with accurate mass measurement.

A new approach to the search for residues of unknown growth promoting agents such as anabolic steroids and -agonists in feed is presented. Following primary extraction and clean-up, samples are separated using gradient liquid chromatography (LC). The effluent is split towards two identical 96-well fraction collectors and an optional electrospray quadrupole time-of-flight mass spectrometry (QTOFMS) system for accurate mass measurement. One 96-well plate is used for a bioassay (enzyme-immuno assay, receptor assay) and will detect the bioactivity and position of the relevant peak in the chromatogram. The positive well in the second 96-well plate is used for identification by LC/QTOFMS/MS. The value of this LC/bioassay/QTOFMS/MS methodology is highlighted by the finding and structure elucidation of a new -agonist in a feed extract.

Enrichment and analysis of nonenzymatically glycated peptides: Boronate affinity chromatography coupled with electron-transfer dissociation mass spectrometry

Nonenzymatic glycation of peptides and proteins by D-glucose has important implications in the pathogenesis of diabetes mellitus, particularly in the development of diabetic complications. However, no effective high-throughput methods exist for identifying proteins containing this low-abundance posttranslational modification in bottom-up proteomic studies. In this report, phenylboronate affinity chromatography was used in a two-step enrichment scheme to selectively isolate first glycated proteins and then glycated, tryptic peptides from human serum glycated in vitro. Enriched peptides were subsequently analyzed by alternating electron-transfer dissociation (ETD) and collision induced dissociation ( CID) tandem mass spectrometry. ETD fragmentation mode permitted identification of a significantly higher number of glycated peptides (87.6% of all identified peptides) versus CID mode (17.0% of all identified peptides), when utilizing enrichment on first the protein and then the peptide level. This study illustrates that phenylboronate affinity chromatography coupled with LC-MS/MS and using ETD as the fragmentation mode is an efficient approach for analysis of glycated proteins and may have broad application in studies of diabetes mellitus.