Yolk–shell magnetic mesoporous TiO₂ microspheres with flowerlike NiO nanosheets for highly selective enrichment of phosphopeptides

Abstract

In this work, we fabricated a yolk-shell magnetic composite that contains mesoporous TiO as the inner shell and flowerlike NiO as the outer shell (denoted as FeO@H-TiO@f-NiO) to reduce the limitations of single-component metal oxides in phosphopeptide enrichment. The NiO nanosheets play a synergistic role in phosphopeptide enrichment. And the unique flowerlike structure of NiO with sufficient space can facilitate the reversible insertion/extraction of peptides, which will have less impact on the enrichment process of the inner TiO shell. The yolk-shell structure and two types of porous nanostructures endowed this composite with a high surface area (156.58 m g) and a large pore volume (0.37 cm g). Owing to the high surface area and combined properties of TiO and NiO, the FeO@H-TiO@f-NiO microspheres showed a better performance for phosphopeptide enrichment than the same material without NiO nanosheets (FeO@H-TiO). According to the LC-MS/MS results, 972 unique phosphopeptides were identified from HeLa cell extracts with a high selectivity (91.9%) by FeO@H-TiO@f-NiO relative to 837 phosphopeptides (selectivity: 60.2%) by FeO@H-TiO. The results demonstrated that, compared with single-component metal oxides, composite metal oxides could enhance the selectivity and sensitivity for phosphopeptide enrichment.

Preparation of Bi0.15Fe0.15TiO2 Nanocomposites for the Highly Selective Enrichment of Phosphopeptides

“…These phenomena can be assigned to the formation of Ti−O−Fe. 54,55 Figure 2 shows the N 2 adsorption−desorption isotherm and the corresponding pore size distributions for the prepared TiO 2 and B 0.15 F 0.15 TN nanocrystal. The specific surface area (10.8 m 2 /g) and pore volume (0.57 cm 3 /g) of the B 0.15 F 0.15 TNs are much higher than those of TiO 2 (4.7 m 2 /g and 0.019 cm 3 /g), respectively, indicating that the doping of Bi and Fe increases the surface area and pore volume.…”

Nanomaterials in Proteomics

“…Liu et al integrated Ti and Zr into MOFs to fabricate binary MOFs with Zr–O and Ti–O units (Figure B), and identified 44 phosphopeptides (34 mono‐ and 10 multiphosphopeptides) from 1 µL of human saliva . Besides, Hong et al integrated TiO 2 and NiO together to fabricate yolk–shell magnetic nanomaterials (Figure C), and identified 972 phosphopeptides from HeLa cell extracts that was better than single‐component metal oxides …”

“…C) Fe 3 O 4 @H–TiO 2 @ f –NiO. Reproduced with permission . Copyright 2017, The Royal Society of Chemistry.…”

In Situ Reduced Multi-Core Yolk–Shell Co@C Nanospheres for Broadband Microwave Absorption

“…Nevertheless, the ordinary design strategies with SiO 2 as a template to form a yolk–shell structure are often too complicated and wasteful. At the same time, the alkaline solution or hydrofluoric acid solution used to etch SiO 2 layer has certain risks and may react with other core or shell materials, These factors all restrict the development of template method [ 25 , 26 , 27 , 28 ].…”