Boronic Acid-Modified Magnetic Fe3O4@mTiO2 Microspheres for Highly Sensitive and Selective Enrichment of N-Glycopeptides in Amniotic Fluid

Abstract

Although mesoporous materials and magnetic materials are used to enrich glycopeptides, materials sharing both mesoporous structures and magnetic properties have not been reported for glycopeptide analyses. Here we prepared boronic acid-modified magnetic Fe3O4@mTiO2 microspheres by covalent binding of boronic acid molecules onto the surfaces of silanized Fe3O4@mTiO2 microspheres. The final particles (denoted as B-Fe3O4@mTiO2) showed a typical magnetic hysteresis curve, indicating superparamagnetic behavior; meanwhile, their mesoporous sizes did not change in spite of the reduction in surface area and pore volume. By using these particles together with conventional poly(methyl methacrylate) (PMMA) nanobeads, we then developed a synergistic approach for highly specific and efficient enrichment of N-glycopeptides/glycoproteins. Owing to the introduction of PMMA nanobeads that have strong adsorption towards nonglycopeptides, the number of N-glycopeptides detected and the signal-to-noise ratio in analyzing standard proteins mixture both increased appreciably. The recovery of N-glycopeptides by the synergistic method reached 92.1%, much improved than from B-Fe3O4@mTiO2 alone that was 75.3%. Finally, we tested this approach in the analysis of amniotic fluid, obtaining the maximum number and ratio of N-glycopeptides compared to the use of B-Fe3O4@mTiO2 alone and commercial SiMAG-boronic acid particles. This ensemble provides an interesting and efficient enrichment platform for glycoproteomics research.

Nanomaterials in Proteomics

“…With the help of hydrophobic poly(methyl methacrylate) (PMMA) nanobeads that were used to remove hydrophobic peptides in HRP digests, the recovery was estimated to be increased from 78% to 90%. This work come up with a good notion of synergistic enrichment, which was used in Shi's report . Moreover, hydrophilic poly(phenol‐formaldehyde resin) and 3‐isocyanatopropyltriethoxysilane were applied to immobilize APBA onto the graphene and zeolitic imidazolate framework‐8, respectively .…”

CPO‐Fe3O4@mTiO2 nanocomposite with integrated magnetic separation and enzymatic and photocatalytic activities in efficient degradation of organic contaminants in wastewater

“…In recent years, some reports of magnetic materials as immobilized enzyme supports have usually involved pre‐modification of Fe 3 O 4. 27, 28 It has been reported that magnetic components can be combined with TiO 2 to form multifunctional nanomaterials 29–32 …”

Boronate affinity monolithic column incorporated with graphene oxide for the in‐tube solid‐phase microextraction of glycoproteins

“…However, because of the inherently low abundance of glycoproteins and the complexity of biological samples, it is almost impossible to directly identify glycoproteins without any pretreatment of samples . Many methods have been developed for glycoprotein enrichment, such as lectin affinity chromatography , HILIC , hydrazide chemistry , and boronate affinity chromatography . Lectin affinity chromatography based on affinity interaction between lectin and glycans shows high specificity.…”

“…However, because Article Related Abbreviations: EGDMA, ethylene glycol dimethacrylate; GO, graphene oxide; HRP, horseradish peroxidase; PEEK, poly(ether ether ketone); poly(VPBA-EGDMA), poly(vinylphenylboronic acid-ethylene glycol dimethacrylate); SWNT, single-walled carbon nanotube; VPBA, vinylphenylboronic acid of the inherently low abundance of glycoproteins and the complexity of biological samples, it is almost impossible to directly identify glycoproteins without any pretreatment of samples [4,5]. Many methods have been developed for glycoprotein enrichment, such as lectin affinity chromatography [6,7], HILIC [8], hydrazide chemistry [9], and boronate affinity chromatography [10,11]. Lectin affinity chromatography based on affinity interaction between lectin and glycans shows high specificity.…”

“…Therefore, the adsorption and desorption of glycoprotein can be easily performed on boronic acid‐based materials by pH manipulation. Various boronate affinity materials have been developed for the enrichment of glycoproteins or glycopeptides, such as boronic acid‐functionalized magnetic nanoparticles , mesoporous silica , molecularly imprinted materials , and monolithic materials . Polymer monoliths are easy to prepare and exhibit good loading capacity, excellent pH stability, and good biocompatibility.…”