Shotgun proteomics are bottom-up proteomic techniques to identify proteins in complex mixture with mass spectrometry.

Multiple fractionation or separation methods are often combined to improve signal-to-noise and proteome coverage and to reduce interference between peptides in quantitative proteomics. Furthermore, a given fractionation method provides additional information on the analytes, such as molecular weight, hydrophobicity or isoelectric point that can be used to improve identification, and to discover protein splice variants or large post-translational modifications.

After cell lysis or isolation, lysates often contain contaminants that are not compatible with downstream steps.

AFFINISEP has developed special tools based on AttractSPE®Disks that can use simply and efficiently for:

  • Desalting :
    Before MS analysis of peptides or proteins, the desalting step is a crucial step to remove salts and purify the peptides/proteins from in-gel and in-solution digests.
    The choice of the sorbent is important as the sorbent will bind peptides and allow salt and other contaminants to be washed off the sample. Then clean peptides and proteins are eluted and analyzed.
  • Fractionation:
    Peptide fractionation is an extremely important and challenging step in proteomics approaches facing more and more complex mixtures.
    The goal is to simplify each fraction for a simplified analysis to extract more information.
  • Detergent removal:
    For a good solubilization of proteins and their digestions, detergents are required.
    These compounds can then affect the peptides/proteins identification and their removal is an important step for greater peptide identification.
  • Exchange buffer.

Several sorbents can be used such as HLB, C18, C8, DVB (hydrophobic), ionic polymers for weak or strong interactions (RPS,SAX, WAX, SCX, WCX)… The product exists under various formats from Stage tips (SPE tips), Spin SPE, 96 Plates SPE (1mL or for microelution) or SPE columns based on disks. If you need to scale-up your purification, the exactly same resin is available under cartridge format.
Several formats are available depending on sample size : SPE tips, 2mL/15mL/50mL spin tubes, cartridges with SPE Disks or 1mL/microelution 96 well plates.

To address the need for high throughput and rapid removal of small molecules from protein sample preparations, we have expanded our offering with 96 SPE Plates.