Determination of Plant Growth Regulators in Vegetable by High Performance Liquid Chromatography-Tandem Mass Spectrometry Coupled with Isotop-coded Derivatization

A method for determination of 6 plant growth regulators by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) coupled with isotope-coded derivatization was developed. d sub(0)-10-Methyl-acridone-2-sulfonyl piperazine (d sub(0)-MASPz, light form) and d sub(3)-10-methyl-acridone-2-sulfonyl piperazine (d sub(3)-MASPz, heavy form) were prepared as isotope-coded derivatization reagents for carboxyl compound. The carboxylic plant growth regulator standards and real samples were derivatized by d sub(0)-MASPz and d sub(3)-MASPz, respectively. The obtained solutions were mixed at a certain ratio, and then injected for HPLC-MS/MS analysis. The light and heavy derivatives were monitored with transitions of [M + H] super(+) arrow right m/z 208.2 and [M + H] super(+) arrow right m/z 211.2, respectively. With heavy derivative as internal standard for corresponding light derivative, the global isotope internal standard quantification for 6 plant growth regulators was achieved. The results indicated that the proposed isotope-coded derivatization method could provide relative quantitative data with adequate linearity in a 10-fold dynamic range (R = 0.9991). The detection and quantitation limits were 0.19-0.34 mu M and 0.53-0.96 mu M, respectively. The relative standard deviations were less than or equal to 3.8%, and the accuracies ranged from 97. 5% to 103.8%.