A protocol for improved extraction of peptides from in-gel protein digests, using a combination of the acid labile surfactant, sodium deoxycholate (SDC) and C18 Empore™ membranes, is presented. This approach results in better mass spectrum quality, higher numbers of identified peptide peaks and improved identification scores compared to standard tryptic digestion protocols, or protocols using only SDC or only C18 Empore™ disks. The advantages of the new protocol are demonstrated for two different types of samples: Merino wool intermediate filament proteins and Elaeis guineensis (oil palm) mesocarp proteins.
2-D electrophoresis MALDI-TOF In-gel digestion
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The authors wish to thank Mrs. Anita Grosvenor for editing this manuscript. Funding for this project was provided by the Foundation for Research Science and Technology (C10X0710).
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