Development of a hydrophilic magnetic amino-functionalized metal-organic framework for the highly efficient enrichment of trace bisphenols in river water samples.

Bisphenols, a typical pollutant with endocrine acting the scientific attention for their ascertained toxicity and wide uses. The magnetic Zr-MOFs (FeO@PDA@UiO-66-NH), functionalized with amino groups and proved by a series of material characterization techniques, were successfully prepared as adsorbents for magnetic solid-phase extraction (MSPE) of five bisphenols (including bisphenol A, bisphenol B, bisphenol S, bisphenol AP and bisphenol AF) from water samples. Liquid chromatography coupled with tandem mass spectrometry was used for sample analysis and quantification.

Preparation of zwitterionic cysteine-modified silica microsphere capillary packed columns for the on-column enrichment and analysis of glycopeptides in human saliva.

In this work, for the first time, -cysteine (-Cys), a zwitterionic hydrophilic compound containing abundant amino and carboxyl was modified on silica microspheres for the fabrication of SiO@-Cys capillary packed column. Since the SiO@-Cys capillary packed column possessed great hydrophilicity brought by -cysteine, they could be utilized to enrich glycopeptides with a low detection limit of 5 fmol μL HRP digests as well as a good selectivity of the mixture of HRP and BSA digests up to a molar ratio of 1:50. The capillary packed column were further applied into the glycosylation analysis of human saliva and 69 glycopeptides were identified from 2 μL human saliva digests.

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.

Integrated Proteome Analysis Device for Fast Single-Cell Protein Profiling.

In our previous work, we have demonstrated an integrated proteome analysis device (iPAD-100) to analyze proteomes from 100 cells. (1) In this work, for the first time, a novel integrated device for single-cell analysis (iPAD-1) was developed to profile proteins in a single cell within 1 h. In the iPAD-1, a selected single cell was directly sucked into a 22 μm i.

Preparation of iminodiacetic acid functionalized silica capillary trap column for on-column selective enrichment of N-linked glycopeptides.

In this work, SiO-IDA microspheres were obtained via a previous method by grafting iminodiacetic acid (IDA) groups onto silica microspheres, then the SiO-IDA microspheres were packed in capillary columns to prepare SiO-IDA capillary trap columns for the first time. Based on the trap columns, a novel on-column enrichment method toward glycopeptides was developed as a sample pretreatment step prior to matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) or nano-LC-MS/MS analysis. The preparation procedures of the trap columns are well reproducible.

Preparation of a TiO-NH modified MALDI plate for on-plate simultaneous enrichment of phosphopeptides and glycopeptides.

In this work, a TiO film was prepared on a MALDI plate by atomic layer deposition (ALD) technique and then modified with -NH. The obtained TiO-NH modified plate was applied for on-plate simultaneous enrichment of phosphopeptides and glycopeptides. The ALD TiO film displayed quite uniform morphology, and attached firmly to the MALDI plate with rather stable physical and chemical properties, which resulted in fine stability of the plate in performance.

Development of immobilized Sn affinity chromatography material for highly selective enrichment of phosphopeptides.

In this work, we first immobilized tin(IV) ion on polydopamine-coated magnetic graphene (magG@PDA) to synthesize Sn -immobilized magG@PDA (magG@PDA-Sn ) and successfully applied the material to highly selective enrichment of phosphopeptides. The material gathered the advantages of large surface area of graphene, superparamagnetism of Fe O , good hydrophilicity and biocompatibility of polydopamine, and strong interaction between Sn and phosphopeptides. The enrichment performance of magG@PDA-Sn toward phosphopeptides from digested β-casein at different concentrations, with and without added digested BSA was investigated and compared with magG@PDA-Ti .

Development of Hf(4+)-immobilized polydopamine-coated magnetic graphene for highly selective enrichment of phosphopeptides.

In this work, we first designed and synthesized an IMAC material with Hf(4+) immobilized on polydopamine-coated magnetic graphene and applied it to phosphopeptides enrichment successfully. The newly prepared material gathered the advantages of large specific surface area of graphene, good hydrophilicity and biocompatibility of polydopamine and superparamagnetism of Fe3O4. We investigated the performance of Hf(4+)-immobilized polydopamine-coated magnetic graphene (denoted as magG@PDA-Hf(4+)) in phosphopeptides enrichment and the results showed high selectivity and sensitivity of the new material.