PredRet: Prediction of Retention Time by Direct Mapping between Multiple Chromatographic Systems
Poster Nov 27, 2015
Jan Stanstrup, Steffen Neumann, Urška Vrhovšek
Demands in metabolomics research have been a key motivator for the development of repositories for MS spectra1,2 and automated tools to aid compound identification3–5. But utilizing only fragmentation is ignoring half of the available information in LC-MS. The retention time (RT) is equally important.
For LC systems there are currently no coordinated efforts to share and exploit information regarding RT. The reason RT information has been neglected is that the RT is specific to the chromatographic system (CS) and there exist no agreed upon RT references.
A database of compound RTs in different CSs was therefore developed. For each pair of CSs, the RTs are used to construct a projection model between the RTs in the two CSs. Building these models between all CSs allowed the prediction of RTs for a high number of compounds in CSs where they had not been experimentally determined.
With the current small database it was possible to predict up to 400 RTs with a median error between 0.01 and 0.11 min depending on the CS. The median width of the confidence interval for predictions ranged from 0.1 to 0.8 min.
The free, open source and web-based tool is available at predret.org.
A New Method for Analyzing MSe/All Ions Fragmentation in Xenobiotic Metabolism StudiesPoster
During early drug discovery, the study of metabolism plays an essential role in determining which drug candidates move forward into development and later stages. As an alternative to traditional Data Dependent Acquisition (DDA), the use of MSE/All Ions Fragmentation (AIF) has become common in metabolite identification workflows for the analysis of metabolic hot spots. Here we present a solution for analysis of MSE/AlF in metID studies.READ MORE
Using Elemental Analysis For Discrimination Of Pinot Noir Wines From Six Different Districts In An AvaPoster
The determination of geographical origin of wine is gaining increased interest by researchers and federal agencies around the world, partially due to increased fraud with regards to place of origin labelling. For wine, multi-elemental profiling of macro, micro, and trace elements has been proposed for determination of authenticity. Commercial wines from different wineries in 5 different neighborhoods within one AVA show characteristic elemental fingerprints. Macro, micro and trace elements as well as elemental ratios contribute to the observed separation, indicating the involvement of multiple factors and underlying mechanisms, including location and soil composition, elemental uptake by vine and rootstock, viticulture and nutrient management, water sources, and small differences in the different wineries.READ MORE
Fast arsenic speciation analysis of wines and rice with LC-ICP-QQQPoster
This method was designed in response to recent and proposed food standards, both international and national, that limit inorganic arsenic rather than total, organic, or individual arsenic species such as arsenite (AsIII) and arsenate (AsV). Analysis time is 10x faster than the current FDA regulatory method, increasing sample throughput, avoided spectral interferences and dramatically increased sensitivity. Validation data from two laboratories demonstrate the method’s accuracy and reproducibility of both wine and rice matrices in a single analytical batch.READ MORE