Magnetic Ti<sub>3</sub>C<sub>2</sub> MXene Nanosheets Prepared for Enrichment of Phosphopeptides
Sen Zhang, Jiayuan Li, Wei Gao, Jun‐qin Qiao, Hong‐zhen Lian
Abstract
MXenes have received lots of attention since discovered and have been applied in various fields. In this work, Ti 3 C 2 –Fe 3 O 4 composites with exposed non-modified Ti 3 C 2 MXene nanosheets were designed and prepared by an in situ growth strategy and then applied in the enrichment of phosphopeptides. The two-dimensional composites could interact with the phosphopeptides through a metal oxide affinity chromatography mechanism provided by Ti–O and Fe–O bonds and a hydrophilic interaction chromatography mechanism by surface hydroxyl groups. This magnetic nanomaterial with a specific surface area of 66.1 m 2 ·g –1 had high sensitivity to phosphopeptides (0.5 nmol·L –1 ) and high selectivity (1:1000 of the molar ratio of β-casein to bovine serum albumin). Non-fat milk was adopted as a real sample to preliminarily examine the applicability of the Ti 3 C 2 –Fe 3 O 4 -based protocol. Subsequently, Qingkailing injection, a kind of traditional Chinese medicine injection, was introduced to further explore the suitability of the nanocomposites for phosphopeptide enrichment from more complex matrices and satisfactory results were obtained.