Advances in hydrophilic nanomaterials for glycoproteomics.

Owing to the formidable challenge posed by microheterogeneities in glycosylation sites, macroheterogeneity of the modification number of glycans, and low abundance and ionization efficiency of glycosylation, the crucial premise for conducting in-depth profiling of the glycoproteome is to develop highly efficient technology for separation and enrichment. The appearance of hydrophilic interaction chromatography (HILIC) has considerably accelerated the progress in glycoproteomics. In particular, additional hydrophilic nanomaterials have been developed for glycoproteomics research in the recent years.

Hydrophilic tripeptide combined with magnetic titania as a multipurpose platform for universal enrichment of phospho- and glycopeptides.

Both of phosphorylation and glycosylation are playing crucial roles in biological processes. For deep analysis of phosphorylation and glycosylation, a multifunctional nanocomposite (dubbed Mag TiO-GSH) is constructed by coating hydrophilic tripeptide on the surface of magnetic titania. The introduction of titanium oxide and hydrophilic tripeptide endows the nanocomposite specific affinity preference towards phospho- and glycopeptides.

Magnetite nanoparticles coated with mercaptosuccinic acid-modified mesoporous titania as a hydrophilic sorbent for glycopeptides and phosphopeptides prior to their quantitation by LC-MS/MS.

A hydrophilic material consisting of a magnetite core coated with mercaptosuccinic acid modified mesoporous titania (denoted as FeO@mTiO-MSA) has been fabricated. It is shown to be a viable sorbent for capturing glycopeptides and phosphopeptides. The sorbent combines the features of metal oxide-based affinity chromatography and of hydrophilic interaction liquid chromatography (HILIC) with the advantages of using mesoporous titania.

A capillary column packed with a zirconium(IV)-based organic framework for enrichment of endogenous phosphopeptides.

A zirconium(IV)-based metal organic framework (Zr-MOF) was deposited on polydopamine-coated silica microspheres to form microspheres of type SiO@PDA@Zr-MOF. These were packed into capillary columns for enrichment of phosphopeptides. The column was off-line coupled to both matrix-assisted laser desorption/ionization time of flight mass spectrometry and LC-ESI-MS/MS.

Synthesis of zwitterionic hydrophilic magnetic mesoporous silica materials for endogenous glycopeptide analysis in human saliva.

A novel zwitterionic hydrophilic magnetic mesoporous silica was prepared for endogenous glycopeptide enrichment prior to MS analysis. For the first time, the material was successfully applied in capturing endogenous glycopeptides from human saliva, indicating great potential of this strategy for glycopeptidome analysis.

Efficient extraction of low-abundance peptides from digested proteins and simultaneous exclusion of large-sized proteins with novel hydrophilic magnetic zeolitic imidazolate frameworks.

Zeolitic imidazolate frameworks (ZIFs) are composed of tetrahedral transition metal ions and imidazolate type organic linkers. This kind of metal organic frameworks (MOFs) combines the unique properties of both zeolites and MOFs. Furthermore, ZIFs can be assembled under mild biocompatible conditions.

Pretreatment Epstein-Barr virus DNA load and cumulative cisplatin dose intensity affect long-term outcome of nasopharyngeal carcinoma treated with concurrent chemotherapy: experience of an institute in an endemic area.

Background: We retrospectively compared the long-term efficacy of concurrent chemoradiotherapy (CCRT) regimens (docetaxel vs. cisplatin), total dose intensity of cisplatin (> 200 vs. ≤ 200 mg/m2) and pretreatment plasma levels of Epstein-Barr virus (EBV) DNA for nasopharyngeal carcinoma (NPC), and investigated the prognostic factors.

Development of oleic acid-functionalized magnetite nanoparticles as hydrophobic probes for concentrating peptides with MALDI-TOF-MS analysis.

The oleic acid-functionalized magnetite nanoparticles (OA-Fe(3) O(4) ) with mean diameter of about 15 nm were synthesized through a low-cost, one-pot method and were designed as hydrophobic probes to realize the convenient, efficient and fast concentration of low-concentration peptides followed by MALDI-TOF-MS analysis. The capability of OA-Fe(3) O(4) nanoparticles in concentration of low-abundance peptides from simple and complex solutions were evaluated by comparing them with a sort of C8-modified magnetic microspheres. Samples of standard peptide solution, protein digest solution and human serum were introduced in the evaluating process, and the OA-Fe(3) O(4) nanoparticles exhibited good surface affinity toward low-concentration peptides.

Selective separation and enrichment of peptides for MS analysis using the microspheres composed of Fe3O4@nSiO2 core and perpendicularly aligned mesoporous SiO2 shell.

In this work, we report the development of a novel enrichment protocol for peptides by using the microspheres composed of Fe(3)O(4)@nSiO(2) Core and perpendicularly aligned mesoporous SiO(2) shell (designated Fe(3)O(4)@nSiO(2)@mSiO(2)). The Fe(3)O(4)@nSiO(2)@mSiO(2) microspheres possess useful magnetic responsivity which makes the process of enrichment fast and convenient. The highly ordered nanoscale pores (2 nm) and high-surface areas of the microspheres were demonstrated to have good size-exclusion effect for the adsorption of peptides.

Preparation of C60-functionalized magnetic silica microspheres for the enrichment of low-concentration peptides and proteins for MALDI-TOF MS analysis.

In this work, for the first time, a novel C60-functionalized magnetic silica microsphere (designated C60-f-MS) was synthesized by radical polymerization of C60 molecules on the surface of magnetic silica microspheres. The resulting C60-f-MS microsphere has magnetite core and thin C60 modified silica shell, which endow them with useful magnetic responsivity and surface affinity toward low-concentration peptides and proteins. As a result of their excellent magnetic property, the synthesized C60-f-MS microspheres can be easily separated from sample solution without ultracentrifuge.

Facile synthesis of C8-functionalized magnetic silica microspheres for enrichment of low-concentration peptides for direct MALDI-TOF MS analysis.

In this study, novel C8-functionalized magnetic polymer microspheres were prepared by coating single submicron-sized magnetite particle with silica and subsequent modification with chloro (dimethyl) octylsilane. The resulting C8-functionalized magnetic silica (C8-f-M-S) microspheres exhibit well-defined magnetite-core-silica-shell structure and possess high content of magnetite, which endow them with high dispersibility and strong magnetic response. With their magnetic property, the synthesized C8-f-M-S microspheres provide a convenient and efficient way for enrichment of low-abundance peptides from tryptic protein digest and human serum.

Enrichment of peptides in serum by C(8)-functionalized magnetic nanoparticles for direct matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis.

Human serum contains a complex array of proteolytically derived peptides (serum peptidome), which contain biomarkers of preclinical screening and disease diagnosis. Recently, commercial C(8)-functionalized magnetic beads (1-10 microm) were widely applied to the separation and enrichment of peptides in human serum, prior to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis. In this work, laboratory-prepared C(8)-functionalized magnetic nanoparticles (about 50 nm) were prepared and applied to the fast separation and the enrichment of peptides from serum.