In this study, the interfacial engineered Fe@FeSi/SiO2 nanocomposite has been synthesized by a one-step route of dc arc-discharge plasma. Higher energy states of Ar/Fe/Si ions in the plasma were also diagnosed by means of online optical emission spectroscopy (OES), supplying energetic information on the configuration of Fe@FeSi nanocapsules embedded in SiO2 matrix. It is indicated that the determined electron temperatures of Ar, Fe, and Si ions are 23 513 K (2.02 eV), 23 225 K (2.00 eV), and 23 063 K (1.99 eV), respectively. Electromagnetic parameters display three prominent resonance peaks at 9.7, 14.3, and 16.8 GHz; these are the result of the synergetic effect of heterogeneous interfaces among the Fe@FeSi/SiO2 nanocomposite. The optimized reflection losses at these resonant frequencies are −33, −20, and −38 dB in certain thicknesses, respectively. The excellent microwave absorption of the Fe@FeSi/SiO2 nanocomposite is readily tunable by consequence of the multiresonance behavior and electromagnetic synergetic effect in the interface-rich nanocomposite. The revealed multiresonance phenomena are significant in the design and fabrication of electromagnetic materials as well the correlative devices, with effective absorption losses at distinctive frequencies.

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Ginsenosides have previously been demonstrated to effectively inhibit cancer cell growth and survival in both animal models and cell lines. However, the specific ginsenoside component that is the active ingredient for cancer treatment through interaction with a target protein remains unknown. By an integrated quantitative proteomics approach via affinity mass spectrum (MS) technology, we deciphered the core structure of the ginsenoside active ingredient derived from crude extracts of ginsenosides and progressed toward identifying the target protein that mediates its anticancer activity. The Tandem Mass Tag (TMT) labeling quantitative proteomics technique acquired 55620 MS/MS spectra that identified 5499 proteins and 3045 modified proteins. Of these identified proteins, 224 differentially expressed proteins and modified proteins were significantly altered in nonsmall cell lung cancer cell lines. Bioinformatics tools for comprehensive analysis revealed that the Ras protein played a general regulatory role in many functional pathways and was probably the direct target protein of a compound in ginsenosides. Then, affinity MS screening based on the Ras protein identified 20(s)-protopanaxadiol, 20(s)-Ginsenoside Rh2, and 20(s)-Ginsenoside Rg3 had affinity with Ras protein under different conditions. In particular, 20(s)-protopanaxadiol, whose derivatives are the reported antitumor compounds 20(s)-Ginsenoside Rh2 and 20(s)-Ginsenoside Rg3 that have a higher affinity for Ras via a low KD of 1.22 μM and the mutation sites of G12 and G60, was demonstrated to play a core role in those interactions. Moreover, the molecular mechanism and bioactivity assessment results confirmed the identity of the chemical ligand that was directly acting on the GTP binding pocket of Ras and shown to be effective in cancer cell bioactivity profiles.

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