Mimosa-Inspired High-Sensitive and Multi-Responsive Starch Actuators

Artificial intelligent actuators are extensively explored for emerging applications such as soft robots, human-machine interfaces, and biomedical devices. However, intelligent actuating systems based on synthesized polymers suffer from challenges in renewability, sustainability, and safety, while natural polymer-based actuators show limited capabilities and performances due to the presence of abundant hydrogen-bond lockers. Here this study reports a new hydrogen bond-mediated strategy to develop mimosa-inspired starch actuators (SA). By harnessing the unique features of gelatinization and abundant hydrogen bonds, these SA enable high-sensitivity and multi-responsive actuation in various scenarios. The non-gelatinized SA can be irreversibly programmed into diverse shapes, such as artificial flowers, bowl shapes, and helix structures, using near-infrared light. Furthermore, the gelatinized SA exhibit reversibly multi-responsive actuation when exposed to low humidity (10.2%), low temperature (37 °C), or low-energy light (0.42 W cm⁻²). More importantly, the SA demonstrate robust applications in smart living, including artificial mimosa, intelligent lampshade, and morphing food. By overcoming the hydrogen-bond lockers inherent in natural polymers, SA open new avenues for next-generation recyclable materials and actuators, bringing them closer to practical applications.     

载银纳米颗粒多响应性复合水凝胶研究进展

近年来载银纳米颗粒多响应性复合水凝胶得到人们的广泛关注。该复合体系通过结合银纳米颗粒与水凝胶,不仅可以利用水凝胶的光学和电学特性,同时也表现出了对温度、pH、介质离子强度的轻微变化以及对某些生物物质浓度变化的快速响应。对近年来载银纳米颗粒多响应性复合水凝胶的性能和分类方法的研究进展进行了详述,介绍了该复合水凝胶在催化领域、生物医学领域、纳米技术和环境污染物质降解等方面的应用。     

Fluorescent multi-responsive cross-linked P(N-isopropylacrylamide)-based nanocomposites for cisplatin delivery

Magnetic, pH and temperature-sensitive, poly(N-isopropylacrylamide) (PNIPAM)-based nanocomposites with fluorescent properties were synthesized by free radical copolymerization-cross linking of NIPAM, N,N-dimethylaminoethyl methacrylate (DMAEMA) and 4-acrylamidofluorescein (AFA). The model anti-cancer drug, cisplatin (CDDP), was loaded into the resulted nanogel. For the production of CDDP-loaded nanocomposite, Fe₃O₄ magnetic nanoparticles (MNPs) and CDDP were loaded into the nanogel. Field-emission scanning electron microscopy (FE-SEM) indicated that the size of nanogel and CDDP-loaded nanocomposite were about 90 and 160?nm, respectively. The encapsulation efficiency of CCDP was found up to 65%. The loaded CCDP showed sustained thermal and pH-responsive drug release. A high level of drug release was observed under the conditions of low pH and high temperature. The lower critical solution temperature (LCST) of synthesized nanogel was about 40?°C. CDDP-loaded nanocomposite showed a volume phase transition from 282 to 128?nm at its LCST. Accordingly, in this study, the synthesized nanocomposite can be employed as a stimuli-responsive anti-cancer drug delivery system and the pH and temperature of solution have the potential to monitor the drug release.