Wu Jinzhe, Ma Zhiyuan, Tang Qianqian, Yang Runhuai
School of Electronic Engineering, Naval University of Engineering, Wuhan 430033, China.
Chaohu Clinical Medical College, Anhui Medical University, Chaohu 238000, China.
Micromachines (Basel). 2025 Jul 1;16(7):788. doi: 10.3390/mi16070788.
Stimulus-responsive hydrogels have broad applications in the biomedical, sensing, and actuation fields. However, conventional fabrication methods are often limited to 2D structures, hindering the creation of complex, personalized 3D hydrogel architectures. Furthermore, hydrogels responding to only a single stimulus and delays in fabrication techniques restrict their practical utility in biomedicine. In this study, we developed two novel multi-stimuli-responsive hydrogels (based on Gelatin/Sodium Alginate and Tannic Acid/EDTA-FeNa complexes) specifically designed for direct ink writing (DIW) 3D printing. We systematically characterized the printed properties and optimized component ratio, revealing sufficient mechanical strength (e.g., tensile modulus: Gel/SA-TA ≥ 0.22854 ± 0.021 MPa and Gel/SA-TA@Fe ≥ 0.35881 ± 0.021 MPa), high water content (e.g., water absorption rate Gel/SA-TA ≥ 70.21% ± 1.5% and Gel/SA-TA@Fe ≥ 64.86% ± 1.28%), excellent biocompatibility (e.g., cell viability: Gel/SA-TA and Gel/SA-TA@Fe ≥ 90%) and good shape memory performance (e.g., the highest shape recovery rate of Gel/SA-TA reaches 74.85% ± 4.776%). Furthermore, we explored electrical characteristics, showing that the impedance value of Gel/SA-TA@Fe hydrogel changes significantly under finger bending and NIR irradiation. This investigation demonstrates the potential of these 3D-printed multi-stimuli hydrogels for applications such as wearable flexible strain sensors.
刺激响应水凝胶在生物医学、传感和驱动领域有着广泛的应用。然而，传统的制造方法通常局限于二维结构，阻碍了复杂、个性化三维水凝胶结构的创建。此外，仅对单一刺激作出响应的水凝胶以及制造技术的滞后限制了它们在生物医学中的实际应用。在本研究中，我们开发了两种新型的多刺激响应水凝胶（基于明胶/海藻酸钠和单宁酸/乙二胺四乙酸铁钠络合物），专门设计用于直接墨水书写（DIW）3D打印。我们系统地表征了打印性能并优化了组分比例，揭示了足够的机械强度（例如，拉伸模量：Gel/SA-TA≥0.22854±0.021MPa和Gel/SA-TA@Fe≥0.35881±0.021MPa）、高含水量（例如，吸水率Gel/SA-TA≥70.21%±1.5%和Gel/SA-TA@Fe≥64.86%±1.28%）、优异的生物相容性（例如，细胞活力：Gel/SA-TA和Gel/SA-TA@Fe≥90%）以及良好的形状记忆性能（例如，Gel/SA-TA的最高形状恢复率达到74.85%±4.776%）。此外，我们探索了电学特性，表明Gel/SA-TA@Fe水凝胶的阻抗值在手指弯曲和近红外照射下会发生显著变化。这项研究证明了这些3D打印的多刺激水凝胶在可穿戴柔性应变传感器等应用中的潜力。
