Lewis-acid surfaces of metal oxides, typically titanium dioxide or zirconium dioxide, that bind phosphate and related oxyanions define metal oxide affinity chromatography (MOAC). Phosphopeptides or phosphoproteins coordinate to the metal centers through their phosphate groups; non-phosphorylated species are washed away, and the bound phosphopeptides are eluted with base or competing anions [1]. Tandem or hybrid materials combine MOAC with immobilized-metal affinity chromatography (IMAC) to broaden coverage, but the MOAC step remains oxide-surface coordination rather than chelated-metal coordination [2]. Conceptual boundaries exclude IMAC on Ni(II)- or Fe(III)-NTA resins, ordinary adsorption chromatography on silica, and ion-exchange chromatography. Essential features are a high-surface-area metal oxide, a loading buffer that favors phosphate–oxide binding, and an elution condition that releases the phosphate without destroying the peptide [3]. Two-dimensional titania–graphene and related nanohybrids are still MOAC so long as the capturing surface is the metal oxide [4].
- metal oxide affinity chromatography
- MOAC
- phosphopeptide
- titanium dioxide
Analytical Chemistry and Chromatography • Spectroscopy • Chemistry • Physical Sciences
References
- Florian Wolschin; Wolfram Weckwerth; Combining metal oxide affinity chromatography (MOAC) and selective mass spectrometry for robust identification of in vivo protein phosphorylation sites. Plant Methods 2005, 1, 9-9, 10.1186/1746-4811-1-9.
- Da-Song Yang; Xi-Ying Ding; Hong-Ping Min; Bo Li; Meng-Xiang Su; Miao-Miao Niu; Bin Di; Fang Yan; Design and synthesis of an immobilized metal affinity chromatography and metal oxide affinity chromatography hybrid material for improved phosphopeptide enrichment. J. Chromatogr. A 2017, 1505, 56-62, 10.1016/j.chroma.2017.05.025.
- Wolfgang Hoehenwarter; Martin Thomas; Ella Nukarinen; Volker Egelhofer; Horst Röhrig; Wolfram Weckwerth; Uwe Conrath; Gerold J. M. Beckers; Identification of Novel in vivo MAP Kinase Substrates in Arabidopsis thaliana Through Use of Tandem Metal Oxide Affinity Chromatography. Mol. Cell. Proteom. 2013, 12, 369-380, 10.1074/mcp.m112.020560.
- Yinghua Yan; Xueni Sun; Chunhui Deng; Yan Li; Xiangmin Zhang; Metal Oxide Affinity Chromatography Platform–Polydopamine Coupled Functional Two-Dimensional Titania Graphene Nanohybrid for Phosphoproteome Research. Anal. Chem. 2014, 86, 4327-4332, 10.1021/ac500047p.