精氨酸功能化磁性纳米材料的制备及在磷酸化肽富集中的应用

Arginine modified magnetic nanoparticles (Mag-Arg) were synthesized and used as the magnetic carrier of magnetic solid phase extraction (MSPE) platform. The prepared magnetic nanoparticles were applied to the enrichment of phosphopeptides from complex samples coupled with MALDI-TOF MS. Mag-Arg was characterized by means of scanning electron microscopy,particle size analysis,Zeta potential measurement, infrared spectroscopy,vibrating sample magnetometer and X-ray diffraction. Under the optimal adsorption de. sorption conditions,the MSPE-MS platform could achieve high selectivity and sensitivity(the detection limit was determined to be as low as 0.1 fmol) for phosphopeptides. Finally,the method was applied to the determination of phosphopeptides in nonfat milk,showing great potential in the detection of low-abundance phospho. peptides in real complex biological samples.