We study the isotope effect by liquid chromatography (LC) with a variety of separation media under reversed and normal phase conditions using the protiated and/or deuterated compounds as the solutes. Results of reversed phase LC (RPLC) suggested that the protiated compounds were more hydrophobic than that of deuterated compounds due to the isotope effect based on the hydrogen bonding between hydrogen atoms of isotopologues and hydroxy groups in the mobile phase. The importance of the hydrogen bonding was also supported by the separation of isotopologues with a silica stationary phase on normal phase LC (NPLC), where the deuterated compounds showed stronger hydrogen bonding to hydroxy groups on silanol. Additionally, we investigated the difference of the strength between CH−π and CD−π interactions. Comparison of free energies of isotopologues by RPLC suggested that the CH−π interaction was slightly stronger than CD−π interaction. Finally, we demonstrated the separation of a few isotopologues on NPLC using a column coated with C70-fullerene, which is capable of strong π-based interactions, by effective CH/CD−π interactions.

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. The first Crn derivative was edge functionalized, which can undergo free inversion of a convex–concave surface. The second Crn derivative was synthesized by modifying the spoke of Crn, which suppresses the convex–concave inversion. Results of LC suggest that each surface showed different shape recognition based on π interaction. Furthermore, the concave surface of Crn showed strong CH−π interaction with a planar molecule, coronene, demonstrated by the shifts of the 1H NMR signals of both Crn and coronene resulting from the multiple interactions between Crn and π electrons in coronene. These results clearly demonstrated the presence of CH−π interactions at multiple points, and the role of shape recognition.

We report the specific intermolecular interactions on C 70fullerene. A newly developed silica-monolithic capillary column, which was modified with C 70 -fullerene via a particular thermal reactive molecule, perfluorophenyl azide, provided a selective retention behavior toward polycyclic aromatic hydrocarbons in liquid chromatography. Especially, a hemispherical molecule, i. e., corannulene, was significantly retained on this C 70 -fullerene column. Results of the computer simulation of the molecules suggested that the specific interaction might be caused by the deflection of the p-electrons-density in C 70 -fullerene. Furthermore, the absorption spectrometry also indicated that the absorption spectra of C 70 -fullerene with/without corannulene were dramatically changed by the specific interaction, whereas no spectrum differences were observed with C 60 -fullerene.

We report the existence of bimodal interactions, the π–π and halogen–π interactions, between the halogenated benzenes and aromatic materials.

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. The compositions of EVs from identical donor cells obtained using the same purification methods may differ, which is a significant obstacle for elucidating objective biological functions. Herein, the potential of a novel lectin-based affinity chromatography (LAC) method to classify EVs based on their glycan structures is demonstrated. The proposed method utilizes a spongylike monolithic polymer (spongy monolith, SPM), which consists of poly(ethylene-co-glycidyl methacrylate) with continuous micropores and allows an efficient in situ protein reaction with epoxy groups. Two distinct lectins with different specificities, Sambucus sieboldiana agglutinin and concanavalin A, are effectively immobilized on SPM without impacting the binding activity. Moreover, high recovery rates of liposomal nanoparticles as a model of EVs are achieved due to the large flow-through pores (>10 μm) of SPM compared to a typical agarose gel. Finally, lectin-immobilized SPMs are employed to classify EVs based on the surface glycan structures and demonstrate different subpopulations by proteome profiling. This is the first approach to clarify the variation of protein contents in EVs by the difference of surface glycans via lectin immobilized media.