title: Analytical properties of solid-substrate electrospray ionization mass spectrometry.
abstract: Conventional electrospray ionization mass spectrometry (ESI-MS) uses a capillary for sample loading and ionization. Along with the development of ambient ionization techniques, ESI-MS using noncapillary emitters has attracted more interest in recent years. Following our recent report on ESI-MS using wooden tips (Anal. Chem. 83, 8201-8207 (2011)), the technique was further investigated and extended in this study. Our results revealed that the wooden tips could serve as a chromatographic column for separation of sample components. Sequential and exhaustive ionization was observed for proteins and salts on wooden tips with salts ionized sooner and proteins later. Nonconductive materials that contain microchannels/pores could be used as tips for ESI-MS analysis with sample solutions loaded to the sharp-ends only, since rapid diffusion of sample solutions by capillary action would enable the tips to become conductive. Tips of inert materials such as bamboo, fabrics, and sponge could be used for sample loading and ionization, while samples such as tissue, mushroom, and bone could form tips to induce ionization for direct analysis with application of a high voltage.
authors.affiliation: State Key Laboratory of Chirosciences, Food Safety and Technology Research Centre and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Hu
authors.forename: Pui-Kin
authors.initials: PK
authors.lastname: So
authors.forename: Zhong-Ping
authors.initials: ZP
authors.lastname: Yao
mesh_terms: D000818:Animals; D002417:Cattle; D002645:Chickens; D004553:Electric Conductivity; D006736:Horses; D057927:Hydrophobic and Hydrophilic Interactions; D010936:Plant Extracts / Q000737:chemistry; D011506:Proteins / Q000737:chemistry; D012965:Sodium Chloride / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation* / Q000379:methods*; D014934:Wood / Q000737:chemistry
chemical_list: D010936:Plant Extracts; D011506:Proteins; D012965:Sodium Chloride