Electrospray-assisted laser desorption/ionization mass spectrometry for continuously monitoring the states of ongoing chemical reactions in organic or aqueous solution under ambient conditions.
Electrospray-assisted laser desorption/ionization (ELDI) combined with mass spectrometry allows chemical and biochemical compounds to be characterized directly from hydrophilic and hydrophobic organic solutions mixed with carbon powders under ambient conditions. Organic and inorganic compounds dissolved in polar or nonpolar solvent such as methanol, tetrahydrofuran, ethyl acetate, toluene, dichloromethane, or hexane can be detected using this ambient ionization technique without prior pretreatment. We have used this technique to monitor the progress in several ongoing reactions: the epoxidation of chalcone in ethanol, the chelation of ethylenediaminetetraacetic acid with copper and nickel ions in aqueous solution, the chelation of 1,10-phenanthroline with iron(II) in methanol, and the tryptic digestion of cytochrome c in aqueous solution. Liquid-ELDI analyses simply require irradiation of the surface of the sample solution with a pulsed ultraviolet laser; the laser energy is adsorbed by the carbon powder presuspended in the sample solution; the absorbed laser energy is then transferred to the surrounding solvent and to the analyte molecules in the solution, leading to their desorption; the desorbed gaseous analyte molecules are then postionized within an electrospray (ESI) plume to generate ESI-like analyte ions.
Cheng
Chi-Yuan
CY
Department of Chemistry, National Sun Yat-Sen University, Kaohsiung, Taiwan.
Yuan
Cheng-Hui
CH
Cheng
Sy-Chyi
SC
Huang
Min-Zong
MZ
Chang
Hui-Chiu
HC
Cheng
Tien-Lu
TL
Yeh
Chen-Sheng
CS
Shiea
Jentaie
J
D002599:Chalcone / Q000737:chemistry; D002614:Chelating Agents / Q000737:chemistry; D004492:Edetic Acid / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry; D006427:Hemin / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry*; D012996:Solutions; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013997:Time Factors; D014867:Water / Q000737:chemistry*
D002614:Chelating Agents; D009930:Organic Chemicals; D012996:Solutions; D014867:Water; D000431:Ethanol; D002599:Chalcone; D006427:Hemin; D004492:Edetic Acid