Can I use RapiGest SF for top-down proteomics? - WKB92026

ENVIRONMENT

• RapiGest SF
• Top-down proteomics

ANSWER

Waters has not evaluated the use of RapiGest for top-down proteomics.

ADDITIONAL INFORMATION

RapiGest SF is designed for bottom-up proteomics, in which it solubilizes a protein to allow better coverage for an enzyme such as trypsin. After digestion with trypsin, acidification of the digestion mixture hydrolizes RapiGest SF to form a nonpolar species and a polar species. Generally, samples are then withdrawn from below the top nonpolar layer.

Use of RapiGest SF to solubilize a protein and then by acidification hydrolize the surfactant has not been studied by Waters.

However, if attempting to use RapiGest SF for top-down proteomics, consider the following suggestions:  

• Acidify the protein sample with RapiGest in 5% formic acid with 25% acetonitrile for 30 minutes at room temperature.  
• Spin the sample down afterwards (take the supernatant liquid for analysis).  
• If using reversed-phase LC/MS for top-down analysis, make sure you bring the acetonitrile concentration to 5% prior to analysis.
• If performing direct infusion onto a mass spec, no adjustment to the acetonitrile concentration is needed.

RapiGest SF Brochure

RapiGest SF Surfactant Care & Use Manual   (lit code 715000122)