In-ESI source hydrogen/deuterium exchange of carbohydrate ions.
We present the investigation of hydrogen/deuterium (H/D) exchange of carbohydrates ions occurring in the electrospray ion source. The shape of the deuterium distribution was observed to be considerably dependent on the temperature of the ion transfer tube and the solvent used. If deuterated alcohol (EtOD or MeOD) or D2O/deuterated alcohol is used as an electrospray solvent, then for high temperatures (>350 °C), intensive back exchange is observed, resulting in ∼30% depth of the deuterium exchange. At low temperatures (<150 °C), the back exchange is weaker and the depth of the deuterium exchange is ∼70%. In the intermediate temperature region (∼250 °C), the deuterium distribution is unusually wide for methanol and bimodal for ethanol. The addition of 1% formic acid results in low (∼30%) depth of the deuterium exchange for any temperature in the operating region. The bimodal distribution for the ethanol can be possibly explained by the presence of differently folded gas-phase ions of carbohydrates.
Institute for Energy Problems of Chemical Physics, Russian Academy of Sciences , Leninskij pr. 38 k.2, 119334 Moscow, Russia.
Yury
Y
Kostyukevich
Alexey
A
Kononikhin
Igor
I
Popov
Eugene
E
Nikolaev
D002241:Carbohydrates / Q000032:analysis*; D003903:Deuterium / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared
D002241:Carbohydrates; D006859:Hydrogen; D003903:Deuterium