Template-free synthesis of uniform magnetic mesoporous TiO2 nanospindles for highly selective enrichment of phosphopeptides

A novel, simple and template-free strategy was developed for the synthesis of uniform magnetic mesoporous TiO2 nanospindles. Unlike previous synthetic approaches which mainly involve the strict control of sol–gel processes, templates, or capping agents, our strategy is based on an additional post-hydrolysis route, giving rise to mesoporous TiO2 with a high surface area (366 m2 g−1). After crystallization, the mesoporous TiO2 nanospindles obtained a high surface area (∼117 m2 g−1) and a large pore size (∼5.4 nm), and exhibited a high magnetic susceptibility (∼18.0 emu g−1), as well as showed a remarkable performance for highly selective and rapid enrichment of phosphopeptides with an unprecedented enrichment capacity of ∼300 mg g−1. These understandings open up a new way for the preparation of functional mesoporous TiO2-based materials with high surface areas in a template-free manner, which is of significant importance for applications from both environmental and industrial points of view.