title: Corona discharge ionization of paracetamol molecule: peak assignment.
abstract: Ionization of paracetamol was investigated using ion mobility spectrometry equipped with a corona discharge ionization source. The measurements were performed in the positive ion mode and three peaks were observed in the ion mobility spectrum. Experimental evidence and theoretical calculations were used to correlate the peaks to related ionic species of paracetamol. Two peaks were attributed to protonated isomers of paracetamol and the other peak was attributed to paracetamol fragment ions formed by dissociation of the N-C bond after protonation of the nitrogen atom. It was observed that three sites of paracetamol compete for protonation and their relative intensities, depending on the sample concentration. The ratio of ion products could be predicted from the internal proton affinity of the protonation sites at each concentration.
authors.affiliation: Chemistry Department, University of Zanjan, Zanjan 45371-38791, Iran. Electronic address: hbahrami@znu.ac.ir.
authors.forename: H
authors.initials: H
authors.lastname: Bahrami
authors.affiliation: Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111, Iran.
authors.forename: H
authors.initials: H
authors.lastname: Farrokhpour
mesh_terms: D000082:Acetaminophen / Q000737:chemistry*; D004583:Electrons; D007477:Ions; D007536:Isomerism; D011522:Protons; D013057:Spectrum Analysis; D013816:Thermodynamics
chemical_list: D007477:Ions; D011522:Protons; D000082:Acetaminophen
keywords: Internal proton affinity; Ion mobility; Paracetamol; Peak assignment