This paper reports chemical modification of silk sericin in LiCl/dimethyl sulfoxide (DMSO) solvent with 4-cyanophenyl isocyanate. Sericin is a highly hydrophilic protein secreted by Bombyx mori, serving as a protein glue in a cocoon. LiCl/DMSO was found to be a good solvent of sericin and useful for homogeneous modification of its abundant hydroxyl groups under nonaqueous condition. Fourier transform infrared (FTIR) analysis of the modified sericins revealed that 4-cyanophenyl groups were incorporated into sericin molecules mainly through urethane linkages. Several characteristics of the modified sericins such as solubility characteristic, hygroscopic property, and thermal stability were investigated. Secondary structure analysis using FTIR spectra suggested that formation of strong intermolecular hydrogen bonds was inhibited by the modification that is probably attributable to the incorporation of bulky 4-cyanophenyl groups. These results demonstrate that chemical modification of sericin using LiCl/DMSO solvent markedly alters its characteristics.
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Nanoscale Horiz
January 2025
Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan 430062, People's Republic of China.
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School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing 211816, China.
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View Article and Find Full Text PDFSmall
January 2025
Beijing Advanced Innovation Center for Intelligent Robots and Systems, School of Medical Technology, Beijing Institute of Technology, Beijing, 100081, P. R. China.
The propensity of zinc (Zn) to form irregular electrodeposits at liquid-solid interfaces emerges as a fundamental barrier to high-energy, rechargeable batteries that use zinc anodes. So far, tremendous efforts are devoted to tailoring interfaces, while atomic-scale reaction mechanisms and the related nanoscale strain at the electrochemical interface receive less attention. Here, the underlying atomic-scale reaction mechanisms and the associated nanoscale strain at the electrochemical alloy interface are investigate, using gold-zinc alloy protective layer as a model system.
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January 2025
School of Chemistry, Dalian University of Technology, Dalian 116024, Liaoning, China.
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View Article and Find Full Text PDFNano Lett
January 2025
Key Laboratory of Physics and Technology for Advanced Batteries, College of Physics, Jilin University, Changchun 130012, China.
Lanthanide-doped fluoride nanocrystals have emerged as promising tools in biomedicine, yet their applications are still limited by their low luminescence efficiency. Herein, we developed highly efficient lithium-based core-shell-shell (CSS) nanoprobes (NPs) featuring a rhombic active domain and a spherical inert protective shell. By introducing Yb as an energy transfer bridge and optimizing the CSS design, a remarkable 1643-fold enhancement in visible emission and a 33-fold increase in NIR emission are achieved compared to original nanoparticles.
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