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instantly monitor, control and stop a reaction at the correct place. Lead diversification could be helped by using a protein to change the reactions of a small molecule that are possible and flow chemistry may lead to a logical flow from synthesis to screening. ‘Pharma needs to do more with less’.


The use of MS in Sports Science has moved on a long way since the white mouse ‘Straub’ test for alkaloids in the 1920’s and 30’s. A recent ruling,WADA 09, lists 12 clauses on prohibited substances and now 34 laboratories in the EU and USA specialise in this complex area using a 50:50 mix of GC- and LC-MS to reach the required selectivity. Typically, as Prof. Mario Thevis (University of Cologne) reported, 15,000 samples per year are analysed. Recent attempts at avoiding detection in sports include the use of rapid acting synthetic insulins and cross-linked haemoglobins that have a much higher uptake of oxygen. Ingenious ways to avoid detection include the use of proteases to degrade proteins prior to analysis – but LC- MS will now detect these via peptide mapping. New drugs of abuse include non- steroidal quinoline, hydantoin types that are highly selective for certain muscle groups.


Prof. Hubertus Irth from the Free University of Amsterdam opened the session relating to Bioanalytical applications with a talk entitled ‘Integration of High-Resolution LC-MS, NMR and on-line screening for the Rapid Discovery and Characterisation of Bioactive Metabolites’ where he talked about the use of Cytochrome P450 BM3 in this field. This molecule has been reported as having the capacity to convert drug, and drug-like molecules into metabolites with interesting drug-like properties. Using this approach allows medicinal chemists working in areas such as early drug discovery with information on so called ‘soft spots’ in scaffold molecules.


Two case studies were presented where Cytochrome P450 BM3 acting as a biocatalyst was applied to screening of focussed library samples. In both cases the direct correlation of accurate molecular mass and affinity data of biotransformation products generated by the Cytochrome P450 BM3 mutants resulted in an efficient workflow to expand focused libraries with interesting novel chemical structures


Metabolomics is being studied by Dr Florence Raynaud at the Institute of Cancer Research, providing successful drug development targeted against specific cancers. A typical profile of biomarkers, peptides and metabolites with QTOF displayed around 100 – 1200 ‘features’, of which around 30-40% were identified. Separation success relies on HPLC column


dimensions and the use of JetStream technology for MS.


Results indicated that on the conventional


system, at 0.4 ml/min, 1324 features were detected, 60% of which showed less than 25% CV. The number of features with CV<25% increased by 16% on the 1290 system and with the same LC conditions and by 45% at 0.6 ml/min. This was the optimal flow rate as the number of features detected decreased and variability increased at higher flow rates with the same gradient. Decreasing the length of the gradient did not improve the number of features or the variability. Peak capacity was also found to be optimal at 0.6 ml/min.


Naturally an over reliance on academic perspectives limits the ability of the research to make areal impact and so the third session was devoted to Industrial perspectives of the topic in hand. Firstly Prof. IanWilson (Astra Zeneca, UK) in his presentation entitled ‘Hyphenation, hyphenation, hyphenation….’ debated the endless, seemingly, opportunities to use hyphenated techniques to obtain better quality information faster. He claimed a world record for linking together an LC systemto UV, IR,MS andNMR spectrometers. Experience of the analysis of complex (often biological) using various combinations of hyphenated techniques were discussed alongside the practical problems and limitations that arise out of the need to analyse complexity.


His final comment was that LC-MS was an answer to many analytical problems but was not THE universal answer and really LC- Anything should never be dismissed.


DrMark Taylor fromPfizer approached Ian Wilson’s strategy when he talked on ‘Improvements to the universality of response of Evaporative Light ScatteringDetection using gas-flow and temperature programming for high-speed LC-MS-UV-ELSDof pharmaceutical compound libraries.’ In promoting the use of Evaporative Light ScatteringDetection (ELSD) as a “universal” quantitative detection system to augment LC-MS, he spoke on how this has now become a routinemethod of analysis to obtain quantitative quality assurance testing of large numbers of liquid file solutions in support of early plate based pharmacology screens. Non-linearity of the ELSDdue to changes in mobile phase composition is known but recent advances in detector design could overcome this. Real-time control over detector variables is not too far away.


Finally closing the session on Industrial Perspectives was Prof. Colin Creaser (Loughborough University, UK) who discussed ‘Combining chromatographic separations with ionmobility spectrometry andmass spectrometry’. Ionmobility spectrometry


(IMS) is an electrophoretic technique in which ionised analytes are separated on the basis of ionmobility in the gas phase in the presence of a buffer gas and under the influence of an electric field. Ionmobility is determined by the charge, reducedmass and collision cross section (i.e. size and shape) of the ion. Two types of IMS were discussed and illustrated using applications of the hyphenated techniques in pharmaceutical and bioanalysis.


Prof FrankDavid (RICand University ofGent, Belgium) reported the use of SPME, alwayswith PDMS fibres for porfilling potentially genotoxic impurties.He noted that these aremore sensitive for later eluting compounds (> heptanes) and that the technique is better than static headspace. There is a list of FDA ‘alerts’ that include boron containing compounds, azides, haloalkanes – both volatile and non- volatile and he showed the use of hexachloroformate derivativisation for amine- containing compounds to give retention onC18 and a greatermass forMS detection.


Dr Tony Bristow (AstraZeneca, UK) –moved onto ‘Evaluation of a new interface to couple gas chromatography to time of flightmass spectrometry - GC-MS and LC-MS on one mass spectrometer’. His work centred upon the use of accuratemass GC-TOF-MS analysis of a series of AZ compounds used in the development of new drugmolecules.


One type of hyphenation that could certainly be regarded as specialist owing to the cost of the spectrometer end would be LC-NMR. Dr Nicolas Haroune (ChemiSPEC, University of Sunderland) gave an entertaining and informative presentation entitled ‘LC-NMR: Why would anyone want to do that?’ He talked on the practical operational details of the technique along with advantages and limitations. Examples were shown illustrating its use to chemical structure problems and how best to use the information alongside that supplied by LC-MS.


Dr Karine Ndjoko (University of Geneva, Switzerland) closed with some interesting work entitled ‘Application of LC-NMR-MS Techniques to the Identification of Bioactive Natural Products’. The advantage of LC-NMR resides not only in the fact that full structural and stereochemical information can be obtained (by the use of 2D NMR) but also in the fact that it is also a highly nonselective detection technique. 1H NMR spectroscopy will detect any hydrogen-containing compound present in the HPLC eluent in a sufficient amount regardless of its structure.


The possibility of using hyphenated techniques does really appear endless and so many possibilities exist to push the information boundary back that the future is extremely positive.


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