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Copyright of China Rubber Industry is the property of Editorial Office of China Rubber Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Synergistic therapeutic effect through the intracellular co-delivery of chemotherapy and biomacromolecule drugs is a novel strategy for improving tumor treatment effectiveness. A triblock copolymer, poly(acrylic acid)-poly(N, Ndiisopropylaminoethyl methacrylate)-poly(N-vinylcaprolactam) (PAA-PDPA-PNVCL), was designed and synthesized for the construction of smart responsive drug carriers. The structure of the polymers was verified by nuclear magnetic resonance spectroscopy (¹H-NMR) and fluorescence spectrophotometer (FL). The transmittances of the polymer solutions under different pH values or temperatures were measured by ultraviolet-visible spectroscopy (UV-Vis). Results showed that the polymer had excellent pH responsiveness and a low critical solution temperature (LCST), which could self-assemble into vesicles with PAA as hydrophilic shell, PDPA as hydrophobic intermediate layer and PNVCL as hydrophilic cavity. Then, the PAA shell layer was crosslinked with disulfide bonds through amide reaction, to improve the structural stability of vesicles and meanwhile introduce the reduction sensitivity. The changes of the particle size, Zeta potential, and morphology of the vesicle under different conditions were studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Results showed that the shell-crosslinked vesicles were uniformly sized spherical structure with good pH value and reduction responsiveness. Their drug encapsulation effect and in-vitro release behavior under different pH values and glutathione (GSH) concentrations were studied by UV-Vis and FT-IR. Results showed that the carriers could achieve zoned and co-loading of hydrophobic small molecule drug (doxorubicin (DOX)) and hydrophilic macromolecular protein drug model (bovine serum protein (BSA)). The hydrophobic layer of PDPA and the crosslinked layer of PAA provided dualblockade for drug leakage. The leakage of drugs under normal physiological conditions was low, and the release of DOX and BSA could only be triggered under simulated tumor microenvironment, that is, weak acid and high concentration of GSH conditions. The smart responsive drug carriers constructed in this paper are expected to achieve co-delivery of chemotherapy and biomacromolecule drugs, which have potential application value to the clinical treatment of tumors. [ABSTRACT FROM AUTHOR]

Chemistry laboratory training is an integral part of chemistry teaching. However, outdated experimental protocols present limitations and can hinder students’ initiative and innate inclination toward exploration. In this study, novel scientific concepts were translated into experimental chemistry teaching. Small fluorescent molecules with aggregation-induced emission and excited-state intramolecular proton transfer properties were prepared using a carbonyl nucleophile addition reaction. The basic photophysical properties of the molecules and their fluorescence response to acid-base stimulation were evaluated experimentally. The non-toxic and non-noxious reagents used for the experiments were refluxed in ethanol for 0.5 h to implement green organic synthesis principles. The experiment was compact and the fluorescence and color changes of the as-synthesized molecules were conspicuous and remarkable. This can stimulate students’ enthusiasm for experimental chemistry. In addition to the basic organic synthesis reaction, this experiment included several modern analysis and characterization methods, such as nuclear magnetic resonance, Fourier-transform infrared spectroscopy, ultraviolet-visible absorption spectroscopy, and fluorescence spectroscopy. We are confident that this intuitive and effective basic experiment can effectively stimulate and cultivate the innate curiosity of students. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)