Selective enrichment of glycopeptides/phosphopeptides using Fe3O4@Au-B(OH)2@mTiO2 core-shell microspheres

Publication date: 1 May 2017
Source:Talanta, Volume 166
Author(s): Dongpo Xu, Guoquan Yan, Mingxia Gao, Chunhui Deng, Xiangmin Zhang
In this work, the bifunctional Fe3O4@Au-B(OH)2@mTiO2 core-shell core-shell microspheres were designed and synthesized for the selective enrichment of glycopeptides/ phosphopeptides. Due to the bifunctional property of the titanium dioxide and the boronic acid group, the microspheres were successfully applied to the enrichment of phosphopeptides and glycopeptides, evaluated by capturing phosphopeptides from tryptic digestion of model phosphoprotein bovine β-casein diluted to 2.0pgμL⁻¹ (8.0×10^–17molμL⁻¹) and glycopeptides from tryptic digestion of model glycoprotein horseradish peroxidase (HRP) diluted to 80pgμL⁻¹ (2.0×10^–15molμL⁻¹). The enrichment selectivity of the bifunctional microspheres was evaluated by capturing phosphopeptides from a peptide mixture of β-casein and bovine serum albumin (BSA) with the molar ratio of 1:1000 (4.2×10^–12mol of β-casein and 4.2×10⁻⁹mol of BSA in 100μL) and glycopeptides from a peptide mixture of HRP and BSA up to the ratio of 1:100 (5.0×10^–12mol of HRP and 5.0×10⁻¹⁰mol of BSA in 100μL).

Graphical abstract

http://ift.tt/2jcFPzN