Development Of Analytical Methods For Determination Of Strigolactones Based On Liquid Chromatography Coupled With Tandem Mass Spectrometry

Strigolactones(SLs),newly identified carotenoid-derived plant hormones,play non-redundant and diverse roles in plant development.SLs can control germination,photomorphogenesis,leaf senescence and root and shoot architecture.Recent years,there are emerging trends in strigolactones research,and it have been established as an important group of plant growth regulators that affect different plant processes.However,Low concentration in plant tissues along with coexistent intricate matrix aggravate the difficulties of the isolation and quantification the of SLs in plants.Nowdays,the information of SLs is still fragmentary,therefore,selective and sensitive methods for the quantification of endogenous SLs in plant tissues are highly desirable to study SLs function.With the continuous development of new analytical instruments and the popularity of mass spectrometry,LC-MS has gradually become the most important tools for SLs analysis.In spite of this,SLs analysis is still challenged by the complexity of plant tissue matrices,the trace amount of endogenous SLs and the low ionization efficiency of MS response of SLs.Therefore,the sample pretreatment step is critical before the analysis is performed.At present,liquid-liquid extraction,solid-phase extraction,HPLC purification has been used for plant roots,stem samples of the pretreatment process.Although these methods are feasible,most of the reported methods existed was time consuming,consuming large amounts of organic solvents,and low extraction yields.Therefore,SLs sample pretreatment with high selectivity and great sensitivity is highlyl diserable.This paper is focuses on the development of fast,sensitive,high-throughput,high-selective method for SLs analysis.1.A solid phase extraction method was introduced for the purification of SLs in plant extracts.By employing a GCB/MAX+MCX(graphite carbon black/mixed-mode anion exchange and mixed-mode cation exchange)double layered solid phase extraction column as the purification medium,hydrophilic interferents and hydrophobic matrix in plant tissue were simultaneously removed.It is simple,rapid and effective to remove the pigment and polar matrix in the plant extract.It is suitable for accurate quantitative analysis of strigolactones in 1 g rice root sample.2.On the basis of the first work,the method of using sulphydryl compounds as derivatization reagent was proposed for the first time,and finally we chose 2-Mercaptopyridine(2-MP)as derivatization reagent.In order to improve the selectivity of pretreatament,the sample was futher passed through MCX solid phase extraction column.By combination of solid phase extraction and chemical derivatization pretreatment method,the method achieved high sensitivity,great selectivity and high throughput.The quantification of endogenous three endogenous strigolactones was achieved in 1 g of phosphorus deficient and normal-cultured rice sample.