GEN-MKT-18-7897-A
Mar 18, 2016 | Blogs, Life Science Research | 0 comments
If you have a TripleTOF® System and you’re using SWATH Acquisition for your quantitative proteomics experiments, you’ve made the right choice. SWATH is a data independent workflow that enables data to be acquired for every detectable analyte in a complex sample. You create a digital map of the sample that can be mined for new information any time new biological insights are hypothesized. It’s all there!
Since the introduction of the workflow at HUPO 2010 in Sydney, Australia, we have been working to further improve the workflow. Optimizations in data acquisition such as smaller and variable Q1 window widths and increased instrument dynamic range have provided increased depth of coverage for your proteomics sample, without compromising reproducibility or data quality.
But what about data processing? Can we improve even further?
The answer is yes! Typically an ion library is used for targeted processing of SWATH data for peptide and protein identification and quantitation. The ion library contains the masses of the peptide ions, sequence-specific fragment ions, relative fragment intensities, and relative retention times, and is easily generated by performing a simple data-dependent acquisition and database search.
In this study, scientists from SCIEX demonstrate that for biological systems that will be studied repeatedly, it is worth taking the extra time to create a deeper ion library as much more information can be extracted from the SWATH acquisition data.
For example, SWATH replicates of a HEK human cell lysate were acquired and processed using three different libraries:
Figure 1. The Impact of Deeper Ion Libraries on Extraction of Quantitative Data from Human Cell Lysate SWATH® Acquisition Data.
As shown in Figure 1, a 118% gain in quantified proteins was observed using a simple ion library (1D HEK) and an extensive ion library (PHL). And the quality and reproducibility of the quantitation are maintained even into the low abundant protein/peptide regime.
A researcher can balance the library generation time with the depth of coverage needed. The three libraries outlined here took increasingly more time to generate. A simple IDA experiment can take only a matter of hours. A 2D fractionation followed by LC-MS/MS on each fraction can be performed in a matter of days. And some groups have invested significantly more time in library generation using multiple cell types and a large degree of fractionation to cover as much of the proteome as possible.
This work also highlights the superior dynamic range of quantitative information that is present in a SWATH Acquisition data file over the traditional data dependent approaches for quantitative proteomics. To read more details of this work, and to see what size
To read more details of this work, and to see what size ion library would make the most sense for your biological system of study, download the full technical note.
The Echo® MS+ system is a novel platform for Acoustic Ejection Mass Spectrometry (AEMS) and combines the speed of acoustic sampling with the selectivity of mass spectrometry. This platform has been designed for high throughput analysis of small and large molecules. The technology combines Acoustic Droplet Ejection (ADE), an Open Port Interface (OPI) and could be coupled with the SCIEX Triple Quad 6500+ system or the ZenoTOF 7600 system.
The Echo® MS+ system comprises of an open-port interface (OPI) and acoustic droplet ejection (ADE) module which could be coupled with a mass spectrometer. The mass spectrometer could either be a SCIEX Triple Quad 6500+ system or the ZenoTOF 7600 system. This non-liquid chromatography based; high-throughput screening platform enables rapid analysis of compounds at speeds of up to 1 sample/second.
The ability to consistently achieve reproducible results on many complex samples across multiple days is critical to a routine clinical laboratory. Laboratories relying on analytical instrumentation require stability and robustness to perform a variety of screening and confirmatory assays with confidence. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) has become the preferred analytical method in the clinical laboratory to reliably perform clinical testing as it provides best-in-class performance and reliability for the most challenging assays. LC-MS/MS offers the required levels of sensitivity and specificity for the detection and quantitation of molecules from complex biological samples, helping laboratories deliver highly accurate data for a variety of clinically relevant analytes across a wide range of assays.
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