title: Simple derivatization of aldehydes with D-cysteine and their determination in beverages by liquid chromatography-tandem mass spectrometry.
abstract: We describe a simple derivatization method to determine aldehydes. This method is based on derivatization with D-cysteine and consecutive liquid chromatography-tandem mass spectrometry (LC-MS/MS). The optimum derivatization conditions of aldehydes with D-cysteine were 10 min at 50°C and pH 7.0. The formed alkyl thiazolidine-4-carboxylic acid derivatives were directly injected in LC-MS/MS. In the established condition, the method was used to detect eight aldehydes in beverages. The limit of detection (LOD) and limit of quantification (LOQ) of the aldehydes were 0.2-1.9 μg L(-1) and 0.7-6.0 μg L(-1) and the relative standard deviation was less than 2.0% at concentrations of 0.1 mg L(-1) and 1.0 mg L(-1) with the exception of octanal. All the beverage samples had detectable levels of methanal (0.033-0.145 mg L(-1)), ethanal (0.085-2.12 mg L(-1)), propanal (ND to 0.250 mg L(-1)), butanal (ND to 0.003 mg L(-1)), pentanal (ND to 0.471 mg L(-1)), hexanal (ND to 0.805 mg L(-1)), heptanal (0.019-3.91 mg L(-1)) and octanal (0.029-0.118 mg L(-1)).
authors.affiliation: Department of Environmental Science, Kongju National University, Kongju 314-701, Republic of Korea.
authors.forename: Hyun-Ji
authors.initials: HJ
authors.lastname: Kim
authors.forename: Ho-Sang
authors.initials: HS
authors.lastname: Shin
mesh_terms: D000447:Aldehydes / Q000032:analysis* / Q000737:chemistry / Q000145:classification; D001628:Beverages / Q000032:analysis*; D002853:Chromatography, Liquid / Q000379:methods*; D003545:Cysteine / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013696:Temperature; D053778:Thiazolidines / Q000737:chemistry
chemical_list: D000447:Aldehydes; D053778:Thiazolidines; C003438:thiazolidine-4-carboxylic acid; D003545:Cysteine