Previous studies on the structural and functional properties of rhodium are based on the face-centered-cubic (fcc) structure in the bulk form. Here we report the first discovery of the hexagonal-close packed (hcp) rhodium in the nanoparticle form. The hcp Rh can be directly synthesized by solvothermal reaction or by electron-beam induced decomposition of Rh monolayers. The hcp Rh nanoparticles are stable under electron beam irradiation. Compared with the fcc structure, the hcp Rh nanoparticles show a large lattice expansion (6% larger atomic volume). The first-principles calculations suggest that the lower surface energy of hcp Rh leads to the size effect in the crystal structure.

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Developments in transition-metal-free trifluoromethylation have attracted broad interests driven by the increasing importance of CF3-containing compounds. Among diverse trifluoromethylation reagents, Togni’s reagents displayed exceptional reactivities, and abundant meaningful organic transformations...

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Radix et Rhizoma Asari is a traditional Chinese medicine, and has many pharmacological effects, such as calming, analgesia, anti-inflammation, antiarrhythmic, antihypertensive, antivirus, etc. But few studies have screened the active compounds from extracts of Radix et Rhizoma Asari for tumor therapy. In this study, a two-dimensional liquid chromatography system was built to screen active compounds acting on epidermal growth factor receptor (EGFR) from Radix et Rhizoma Asari. The screening result showed that asarinin from Radix et Rhizoma Asari was the targeted component that could act on EGFR specificity. The competitive binding assay and molecular docking assay results showed asarinin binding with EGFR in similar manner as with gefitinib, which was used as a positive control drug. Then the antitumor effect of asarinin was studied through cell growth assay in vitro. The results showed that gefitinib and asarinin could inhibit highly expressed EGFR cell growth in a dose-dependent manner in the range of dose from 0.10 to 102.4 μM. This two-dimensional liquid chromatography system will be a useful method in drug discovery from natural medicinal herbs for searching potential antitumor candidates.

Carthamus tinctorius, used in traditional Chinese medicine, has many pharmacological effects, such as anticoagulant effects, antioxidant effects, antiaging effects, regulation of gene expression, and antitumor effects. However, there is no report on the antiallergic effects of the components in C. tinctorius. In the present study, we investigated the antiallergic components of C. tinctorius and its mechanism of action. A rat basophilic leukemia 2H3/cell membrane chromatography coupled online with high-performance liquid chromatography and tandem mass spectrometry method was developed to screen antiallergic components from C. tinctorius. The screening results showed that Hydroxysafflor yellow A, from C. tinctorius, was the targeted component that retained on the rat basophilic leukemia 2H3/cell membrane chromatography column. We measured the amount of β-hexosaminidase and histamine released in mast cells and the key markers of degranulation. The release assays showed that Hydroxysafflor yellow A could attenuate the immunoglobulin E induced release of allergic cytokines without affecting cell viability from 1.0 to 50.0 μM. In conclusion, the established rat basophilic leukemia 2H3 cell membrane chromatography coupled with online high-performance liquid chromatography and tandem mass spectrometry method successfully screened and identified Hydroxysafflor yellow A from C. tinctorius as a potential antiallergic component. Pharmacological analysis elucidated that Hydroxysafflor yellow A is an effective natural component for inhibiting immunoglobulin E-antigen-mediated degranulation.