Hi Niall, In the labs I've worked in, we've generally added a mix of 6-8 internal standards for untargeted LC-MS; these have often spanned the range of chromatographic retention and mass ranges. We used them to evaluate retention time stability, mass accuracy, changes in instrument performance over time (i.e. loss of signal), and matrix effect.
If you are in Manchester, you could go speak with the metabolomics folks at Manchester University. They have a lot of experience in mass spec and could give you some good advice.
Background We are inviting 6 early-career researchers to join the Metabolomics Society's Early-career Members Network (EMN) Committee. The mission of the EMN is to recognize the value and importance of our early-career members, to ensure that their views are heard and acted upon, and to ultimately improve their experience in metabolomics science and our community. Current programs and activities offered by the EMN include: workshops and the EMN Reception at the annual Metabolomics conference, the EMN Webinar Series, and the EMN Travel Bursary Program. We are also involved in the Metabolomics Forum and have a Facebook profile to stay connected with the membership. We are looking for creative thinkers to identify challenges faced by early-career researchers in metabolomics and to develop programs to overcome these challenges.
Eligibility We welcome applications from students conducting higher degrees (Masters, PhDs) in a metabolomics discipline or from those within 5 years of their PhD who are actively engaged in metabolomics science. As an international society we encourage applications from all continents. Successful applicants must be members of the Metabolomics Society (or immediately become members upon joining the task group).
Time Commitment There is much exciting work to be done and much to achieve! Therefore we anticipate a contribution of up to two hours per week (on average). If the Early-career Members Network organises sessions at conferences or other events, time commitments will increase accordingly. Note also that the existing members of the EMN Committee span many time zones, so some conference calls may occur early or late in the day. No dedicated travel will be required for the EMN Committee discussions. The appointment to the EMN Committee is for one year initially, and may be extended up to two years. It is your responsibility to discuss this commitment with your supervisor(s) prior to applying.
One-page CV with relevant experience in developing and leading networking activities (e.g., student rep for other societies) plus your research experience in metabolomics (e.g., presentations, publications, etc.). If you are currently a member, please provide your membership number to us as well.
Up to 300 words on why you fit the role and up to an additional 300 words (one page in total) on what ideas you are passionate about developing as part of the Early-career Members Network. Applications will then be reviewed by members of the existing EMN committee members, and successful candidates will be notified by the end of September 2017 to start in October 2017.
I know someone who had the same experience and they were advised that Windows 10 has not been tested thoroughly for Xcalibur, so it's not supported yet. That person went back to Windows 7 for the time being.
The normalization methods listed are to deal with dilution effects. Some people use these methods to normalize the effect of hydration in plasma/serum, for example. There are certain assumptions associated with those methods, so you should read up on them before you use them. Depending on your sample type, there are other ways to normalize your data (dry/wet weight for tissue, cell count, total signal, etc).
In terms of using area under peaks or max peak height, I think most often you would use area. From my understanding, max peak height is used more for when you have atypical peak shapes ("saw-tooth" peaks). It would be best to have a chat with an analytical chemist about this.
Lee Kong Chian School of Medicine (Singapore) invites applications for: Postdoctoral Research Fellow in Lipidomics/ Systems Biology of Metabolism during Infection and Immunity (Laboratory of Assistant Professor Xue Li Guan)
For GC-MS, you could try the AnalyzerPro software from SpectralWorks in the UK. I haven't tried it and it's not free, but I've heard good things. If you're new to this type of analysis, it will probably be a lot more user friendly than R packages. http://www.spectralworks.com/products/analyzerpro/