具有两性离子聚合物水凝胶填充的生物相容核壳型微针传感器,用于快速连续经皮监测。
Biocompatible Core-Shell Microneedle Sensor Filled with Zwitterionic Polymer Hydrogel for Rapid Continuous Transdermal Monitoring.
机构信息
Department of Bioengineering, The University of Tokyo, Tokyo 113-8654, Japan.
Sanyo Chemical Industries, Ltd., Kyoto 605-0995, Japan.
出版信息
ACS Nano. 2024 Oct 1;18(39):26541-26559. doi: 10.1021/acsnano.4c02997. Epub 2024 Sep 19.
Microneedle (MN)-based electrochemical biosensors hold promising potential for noninvasive continuous monitoring of interstitial fluid biomarkers. However, challenges, such as instability and biofouling, exist. This study proposes a design employing hollow MN to encapsulate a zwitterionic polymer hydrogel sensing layer with excellent biocompatibility and antifouling properties to address these issues. MN shell isolates the internal microporous sensing layer from subcutaneous friction, and the hydrogel filling leverages the MNs' three-dimensional structures, enabling high-dense loading of biorecognition elements. The hollow MNs are successfully fabricated from high-molecular-weight polylactic acid via drawing lithography, exhibiting sufficient strength for effective epidermis penetration. Additionally, a high-performance gold nanoconductive layer is successfully deposited inside the MN hollow channel, establishing a stable electrical connection between the polymer MN and the hydrogel sensing layer. To support the design, numerical simulations of position-based diffusive analyte solutes reveal fast-responsive electrochemical signals attributed to the high diffusion coefficient of the hydrogel and the concentrated structure of the hollow channel encapsulation. Experimental results and numerical simulations underscore the advantages of this design, showcasing rapid response, high sensitivity, long-term stability, and excellent antifouling properties. Fabricated MN sensors exhibited biosafety, feasibility, and effectiveness, with accurate and rapid in vivo glucose monitoring ability. This study emphasizes the significance of rational design, structural utilization, and micro-nanofabrication to unlock the untapped potential of MN biosensors.
基于微针(MN)的电化学生物传感器在非侵入式连续监测间质液生物标志物方面具有很大的潜力。然而,存在一些挑战,如不稳定性和生物污损。本研究提出了一种设计,采用空心 MN 来封装具有良好生物相容性和抗污损性能的两性离子聚合物水凝胶传感层,以解决这些问题。MN 壳将内部微孔传感层与皮下摩擦隔离开来,水凝胶填充利用 MN 的三维结构,实现了生物识别元件的高密度负载。空心 MN 是通过拉伸光刻法从高分子量聚乳酸成功制造的,具有足够的强度,可有效穿透表皮。此外,成功地在 MN 空心通道内沉积了高性能的金纳米导电层,在聚合物 MN 和水凝胶传感层之间建立了稳定的电连接。为了支持该设计,基于位置的扩散分析物溶质的数值模拟揭示了快速响应的电化学信号,这归因于水凝胶的高扩散系数和空心通道封装的浓缩结构。实验结果和数值模拟突出了这种设计的优势,展示了快速响应、高灵敏度、长期稳定性和优异的抗污损性能。制造的 MN 传感器表现出生物安全性、可行性和有效性,具有准确和快速的体内葡萄糖监测能力。本研究强调了合理设计、结构利用和微纳制造的重要性,以挖掘 MN 生物传感器的未开发潜力。