High-Recovery Desalting Tip Columns for a Wide Variety of Peptides in Mass Spectrometry-Based Proteomics.

In mass spectrometry-based proteomics, loss-minimized peptide purification techniques play a key role in improving sensitivity and coverage. We have developed a desalting tip column packed with thermoplastic polymer-coated chromatographic particles, named ChocoTip, to achieve high recoveries in peptide purification by pipet-tip-based LC with centrifugation (tipLC). ChocoTip identified more than twice as many peptides from 20 ng of tryptic peptides from Hela cell lysate compared to a typical StageTip packed with chromatographic particles entangled in a Teflon mesh in tipLC.

Centrifugal Gel Crushing Tips for Gel-Based Proteome Analysis.

We have developed a centrifugal gel-crushing method using a pipet tip. Polyacrylamide gel slices are extruded from the narrowing cavity of a pipet tip by centrifugation in a few minutes to crush them into pieces of appropriate size. The size of the crushed gel could be controlled by several parameters, including centrifugal force and pipet tip cavity.

TurboID-EV: Proteomic Mapping of Recipient Cellular Proteins Proximal to Small Extracellular Vesicles.

Extracellular vesicles (EVs), including exosomes, have been recognized as key mediators of intercellular communications through donor EV and recipient cell interaction. Until now, most studies have focused on the development of analytical tools to separate EVs and their applications for the molecular profiling of EV cargo. However, we lack a complete picture of the mechanism of EV uptake by the recipient cells.

Rapid and Highly Efficient Purification of Extracellular Vesicles Enabled by a TiO Hybridized Spongy-like Polymer.

We developed a novel purification medium of extracellular vesicles (EVs) by constructing a spongy-like monolithic polymer kneaded with TiO microparticles (TiO-hybridized spongy monolith, TiO-SPM). TiO-SPM was applied in a solid-phase extraction format and enabled simple, rapid, and highly efficient purification of EVs. This is due to the high permeability caused by the continuous large flow-through pores of the monolithic skeleton (median pore size; 5.

Efficient Selective Adsorption of SARS-CoV-2 via the Recognition of Spike Proteins Using an Affinity Spongy Monolith.

Since the outbreak of COVID-19, SARS-CoV-2, the infection has been spreading to date. The rate of false-negative result on a polymerase chain reaction (PCR) test considered the gold standard is roughly 20%. Therefore, its accuracy poses a question as well as needs improvement in the test.

Rational Supramolecular Strategy via Halogen Bonding for Effective Halogen Recognition in Molecular Imprinting.

Halogen bonding is a highly directional interaction and a potential tool in functional material design through self-assembly. Herein, we describe two fundamental supramolecular strategies to synthesize molecularly imprinted polymers (MIPs) with halogen bonding-based molecular recognition sites. In the first method, the size of the σ-hole was increased by aromatic fluorine substitution of the template molecule, enhancing the halogen bonding in the supramolecule.

Rational Strategy for Space-Confined Atomic Layer Deposition.

Atomic layer deposition (ALD) offers excellent controllability of spatial uniformity, film thickness at the Angstrom level, and film composition even for high-aspect-ratio nanostructured surfaces, which are rarely attainable by other conventional deposition methodologies. Although ALD has been successfully applied to various substrates under open-top circumstances, the applicability of ALD to confined spaces has been limited because of the inherent difficulty of supplying precursors into confined spaces. Here, we propose a rational methodology to apply ALD growths to confined spaces (meter-long microtubes with an aspect ratio of up to 10 000).

Classification of Extracellular Vesicles Based on Surface Glycan Structures by Spongy-like Separation Media.

Extracellular vesicles (EVs) are lipid bilayer vesicles that enclose various biomolecules. EVs hold promise as sensitive biomarkers to detect and monitor various diseases. However, they have heterogeneous molecular compositions.

Moderate molecular recognitions on ZnO -plane and their selective capture/release of bio-related phosphoric acids.

Herein, we explore the hidden molecular recognition abilities of ZnO nanowires uniformly grown on the inner surface of an open tubular fused silica capillary liquid chromatography. Chromatographic evaluation revealed that ZnO nanowires showed a stronger intermolecular interaction with phenylphosphoric acid than any other monosubstituted benzene. Furthermore, ZnO nanowires specifically recognized the phosphate groups present in nucleotides even in the aqueous mobile phase, and the intermolecular interaction increased with the number of phosphate groups.

Fluorescent detection of target proteins a molecularly imprinted hydrogel.

Proteins are typically separated by an immune reaction, such as an enzyme-linked immunosorbent assay, and are detected by selective fluorescent labeling. This has potential for complicated procedures and the denaturation of proteins by labeling, and is cost consuming. In this study, we propose a technique for the selective separation and detection of a target protein using a molecularly imprinted hydrogel (PI gel) with fluorescent monomers.

Rational Strategy for Space-Confined Seeded Growth of ZnO Nanowires in Meter-Long Microtubes.

Seeded crystal growths of nanostructures within confined spaces offer an interesting approach to design chemical reaction spaces with tailored inner surface properties. However, such crystal growth within confined spaces tends to be inherently difficult as the length increases as a result of confinement effects. Here, we demonstrate a space-confined seeded growth of ZnO nanowires within meter-long microtubes of 100 μm inner diameter with the aspect ratio of up to 10 000, which had been unattainable to previous methods of seeded crystal growths.

Separation of saccharides using fullerene-bonded silica monolithic columns via π interactions in liquid chromatography.

We report on a potential method to separate sugars by using the specific interaction between fullerenes and saccharides in liquid chromatography (LC). Aromatic rings with high electron density are believed to interact strongly with saccharides due to CH-π and/or OH-π interactions. In this study, the fullerene-bonded columns were used to separate saccharides by LC under aqueous conditions.

Separation of halogenated benzenes enabled by investigation of halogen-π interactions with carbon materials.

The halogen-π (X-π) interaction is an intermolecular interaction between the electron-poor region of bonded halogen atoms and aromatic rings. We report an experimental evaluation of the halogen-π (X-π) interaction using liquid chromatography with carbon-material coated columns providing strong π interactions in the normal phase mode. A C-fullerene (C70)-coated column showed higher retentions for halogenated benzenes as the number of halogen substitutions increased as a result of X-π interactions.

Tunable Liquid Chromatographic Separation of H/D Isotopologues Enabled by Aromatic π Interactions.

We report hydrogen/deuterium (H/D) isotope effects based on weak intermolecular interactions with polar functional groups and aromatic rings in liquid chromatography (LC). Various LC experiments with different aromatic analytes, separation media, and nonpolar mobile phases were conducted under normal phase LC conditions, where the hydrophobic interaction was completely suppressed. The separation media that had polar functional groups, such as silanol groups, allowed for higher separation efficiencies for the pairs of aromatic H/D isotopologues.

Differentiating π Interactions by Constructing Concave/Convex Surfaces Using a Bucky Bowl Molecule, Corannulene in Liquid Chromatography.

Convex-concave π conjugated surfaces in hemispherical bucky bowl such as corannulene (Crn) have shown increasing utility in constructing self-assembled new functional materials owing to its unique π electrons and strong dipole. Here, we investigate these specific molecular recognitions on Crn by developing new silica-monolithic capillary columns modified with Crn and evaluating their performance in the separation of different aromatic compounds by liquid chromatography (LC). We synthesized two Crn derivatives and conjugated them onto the surface of a silica monolith.