Accurate Protein Mass Estimation

Whole Protein Molecular Weight Analysis

This service determines the accurate mass of a protein by nLC-MS analysis on a state of the art Q-TOF MS system.

The protein sample has to be reasonably pure and prepared in a low salt based buffer but detergent free. It is then trapped onto a reverse phase C8 column (RPC) and desalted prior to elution off the column by an increasing concentration of organic solvent e.g. Acetonitrile or Methanol.

As the protein is introduced into the mass spectrometer via the electrospray source it becomes protonated by gaining a variable number of positive charges. The mass spectrometer then separates the protein based on the number of charges it has gained into a charged based envelope. A specialised algorithm called Maximum Entropy (MaxEnt) is then used to de-convolute the charged based envelope into a mass based spectra.

A report containing the spectra is supplied to the user either in powerpoint or as a PDF by email or as hardcopy (if requested).