Abstract: A method for the analysis of gibberellin A1 (GA1), gibberellin A3 (GA3) and gibberellin A4 (GA4) in Arabidopsis thaliana by matrix solid-phase dispersion extraction (MSPD) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed. The solid sample of Arabidopsis thaliana was gently blended with C18 to obtain a homogeneous mixture. This mixture was transferred to an SPE cartridge filled with 0.5 g C18 to form a MSPD column. GA1, GA3 and GA4 were eluted with cold 80% methanol aqueous solution. The target compounds were separated on a C18 column with a gradient elution of 0.05% formic acid aqueous solution and acetonitrile as the mobile phase. The identification and quantification were carried out by using electrospray ionization in negative ion mode (ESI~) with multiple reaction monitoring (MRM). The linear ranges for GA1, GA3 and GA4 were all from 10 to 300 ng/g with correlation coefficients greater than 0.98. The limits of detection were in the range of 1.1~4.1 ng/g. The average recoveries and relative standard deviations were 54.7%~102.6% and 3.2%~12.8% respectively in the spiked range of 10~50 ng/g. The method is simple, sensitive, efficient and accurate. It is suitable for the confirmation and quantitative determination of GA1, GA3 and GA4 in Arabidopsis thaliana.

Key words: Arabidopsis thaliana, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), gibberellins, matrix solid-phase dispersion extraction