- High production of small organic dicarboxylate dianions by DESI and ESI.
High production of small organic dicarboxylate dianions by DESI and ESI.
Journal of the American Society for Mass Spectrometry (2015-01-18)
Yonghui Dong, Graziano Guella, Fulvio Mattivi, Pietro Franceschi
PMID25595095
ABSTRACT
A significant production of gas-phase dicarboxylate dianions has been observed in standard ESI and DESI during the analysis of small organic dicarboxylic acids under moderate or highly alkaline conditions. In ESI, this can be attributed to an excess of hydroxyl ions (OH(-)) which favor the formation of an high amount of dianions in solution, contemporarily trapping the potential counter ions during the ESI process. The results obtained in DESI highlight the role of the surface in trapping the counter-ions during desorption process and determining the ultimate nature of the observed gas-phase ions.
MATERIALS
Product Number
Brand
Product Description
Sigma-Aldrich
Sodium hydroxide, puriss., meets analytical specification of Ph. Eur., BP, NF, E524, 98-100.5%, pellets
Sigma-Aldrich
Sodium hydroxide, puriss. p.a., ACS reagent, reag. Ph. Eur., K ≤0.02%, ≥98%, pellets
Sigma-Aldrich
Acetonitrile solution, contains 0.1 % (v/v) trifluoroacetic acid, suitable for HPLC
Supelco
Residual Solvent - Acetonitrile, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
Sodium hydroxide, anhydrous, free-flowing, Redi-Dri™, reagent grade, ≥98%, pellets