Processing capacity and product yield of three-dimensional (3D) smart responsive carriers are markedly superior to those of two-dimensional substrates with the same compositions due to the special structure; therefore, more attempts have been made to develop the 3D intelligent systems in recent decades. A novel preparation strategy of thermoresponsive glass sphere-based composite carriers was reported in this study. First, PNIPAAm copolymers were synthesized by free-radical polymerization of N -isopropylacrylamide (NIPAAm), hydroxypropyl methacrylate (HPM), and 3-trimethoxysilypropyl methacrylate (TMSPM). Then, the copolymer solution was sprayed on the surfaces of glass spheres using a self-made bottom-spray fluidized bed reactor, and the bonding between copolymers and glass spheres was fabricated by thermal annealing to form PNIPAAm copolymer/glass sphere composite carriers. The coating effects of PNIPAAm copolymers on sphere surfaces were investigated, including characteristic functional groups, surface microstructure, grafting density, equilibrium swelling, as well as biocompatibility and potential application for cell culture. The results show that the temperature-responsive PNIPAAm copolymers can be linked to the surfaces of glass spheres by bottom-spray coating technology, and the copolymer layers can be formed on the sphere surfaces. The composite carriers have excellent thermosensitivity and favorable biocompatibility, and they are available for effective cell adhesion and spontaneous cell detachment by the use of smart responsiveness. Graphical abstract Preparation of thermoresponsive glass sphere-based composite carriers via bottom-spray coating technology.

中文翻译：

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热响应性复合载体的制备和表征：PNIPAAm接枝的玻璃球

三维（3D）智能响应载体的处理能力和产品产量由于其特殊的结构而明显优于具有相同成分的二维基材。因此，近几十年来人们为开发3D智能系统做出了更多的尝试。在这项研究中报道了一种新型的基于热敏玻璃球的复合载体的制备策略。首先，通过N-异丙基丙烯酰胺（NIPAAm），甲基丙烯酸羟丙酯（HPM）和甲基丙烯酸3-三甲氧基甲硅烷基丙基酯的自由基聚合反应合成PNIPAAm共聚物。然后，使用自制的底部喷雾流化床反应器将共聚物溶液喷涂在玻璃球表面上，通过热退火制备共聚物与玻璃球的键合，形成PNIPAAm共聚物/玻璃球复合载体。研究了PNIPAAm共聚物在球体表面的涂层效果，包括特征性官能团，表面微结构，接枝密度，平衡溶胀以及生物相容性和细胞培养的潜在应用。结果表明，通过底部喷涂技术可以将温度响应性PNIPAAm共聚物连接到玻璃球的表面，并且可以在玻璃球的表面形成共聚物层。复合载体具有优异的热敏性和良好的生物相容性，并且通过利用灵敏的响应性，可用于有效的细胞粘附和自发的细胞分离。