Hydrophobic Treatment Enabling Analysis of Wettable Surfaces using a Liquid Microjunction Surface Sampling Probe/Electrospray Ionization-Mass Spectrometry System

Journal Article · Sat Jan 01 00:00:00 EST 2011 · Analytical Chemistry

DOI:https://doi.org/10.1021/ac102634e· OSTI ID:1081682

Walworth, Matthew J ^[1]; Stankovich, Joseph J ^[1]; Van Berkel, Gary J ^[1]; Schulz, Michael ^[2]; Minarik, susanne ^[2]; Nichols, Judy ^[3]; Reich, Eike ^[4]

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1. ORNL
2. Merck Research Laboratories
3. CAMAG Scientific, Inc., Wilmington, NC
4. CAMAG Laboratory, Switzerland

An aerosol application procedure involving one or more commercially available silicone based products was developed to create hydrophobic surfaces that enable analysis of otherwise wettable, absorbent surfaces using a liquid microjunction surface sampling probe/electrospray ionization mass spectrometry system. The treatment process resulted in a hydrophobic surface that enabled formation of the requisite probe - to - surface liquid microjunction for sampling and allowed efficient extraction of the analytes from the surface, but did not contribute significant chemical background in the mass spectra. The utility of this treatment process was demonstrated with the treatment of wettable high performance thin layer chromatography plates, post plate development, and their subsequent analysis with the sampling probe. The surface treatment process for different surface types was described and explained and the effectiveness of the treatment and subsequent analysis was illustrated using alkaloids from Goldenseal (Hydrastis canadensis) root separated on a normal phase silica gel 60 F254S plate and peptides from protein tryptic digests separated on a Protochrom HPTLC Silica gel 60 F254S plate and a Protochrom HPTLC cellulose sheet. This simple surface treatment process significantly expands the analytical surfaces that can be analyzed with the liquid microjunction surface sampling probe, and therefore, also expands the analytical utility of this liquid extraction based surface sampling approach.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1081682
• Journal Information: Analytical Chemistry, Vol. 83, Issue 2; ISSN 0003--2700
• Country of Publication: United States
• Language: English