先进的光纤表面等离子体共振（SPR）乳酸生物传感平台：基于折射率变化、酶功能化及多层自组装实现pH值反馈控制

《Biosensors and Bioelectronics》：Advanced Fiber Optic SPR Lactate Biosensing Platform: Based on RI Variation, Enzymatic Functionalization, and Multi-Layer Self-Assembly pH Feedback

基于表面等离子体共振（SPR）技术，开发了三种乳酸检测探针（SPR-1至SPR-3），分别利用折射率变化、LDH修饰及多层酶自组装-PH响应机制，实现从超低浓度到高浓度的宽范围检测，灵敏度达14.455 nm/mM，检测限0.71 μM，较传统方法提升三个数量级，为疾病诊断和代谢监测提供新工具。

　　

Mingshi Song|Xili Jing|Zhiyong Yin|Shuguang Li|Jianshe Li|Linchuan Hu|Tianli Huo

中国河北省燕山大学理学院，亚稳态材料科学与技术国家重点实验室及微观结构材料物理重点实验室，秦皇岛市，066004

摘要

由于精准医疗的需求，对纳米摩尔到微摩尔浓度范围内的乳酸进行敏感且选择性的定量检测一直是生物传感领域长期面临的挑战。本研究介绍了三种基于表面等离子体共振（SPR）技术的乳酸浓度传感探针：利用折射率（RI）变化（SPR-1）、乳酸脱氢酶（LDH）修饰（SPR-2）以及多层酶自组装pH响应机制（SPR-3）。这些探针能够在高、低和超低浓度范围内实现乳酸的检测。比较各传感器的性能发现，SPR-2在mM浓度范围内具有1.11 nm/mM的检测灵敏度，并表现出目标选择性。在此基础上，SPR-3通过逐层自组装技术集成了酶-PH反馈机制，显著提高了灵敏度和选择性。该传感器对超低浓度乳酸的响应能力尤为突出，其灵敏度达到14.455 nm/mM，是SPR-1的218.86倍、SPR-2的13.02倍；检测限（LOD）比传统设计提高了三个数量级。通过改变自组装层的结构，共振波长范围可在466 nm至749 nm之间动态调节，检测灵敏度覆盖11.678 nm/mM至16.122 nm/mM。其在超低浓度乳酸检测方面的卓越性能展示了其在疾病诊断、代谢监测及相关领域的广泛应用潜力。

章节摘录

引言

乳酸是糖酵解途径的关键产物，通过丙酮酸的还原在哺乳动物细胞的细胞质中产生，从而在缺氧条件下维持糖酵解过程。乳酸的产生与清除之间的动态平衡反映了细胞的氧化还原稳定性，其浓度变化与身体的能量代谢、氧气供应和酸碱平衡密切相关[1][2][3][4]。乳酸具有较低的分子量和较高的水溶性，能够快速

SPR传感原理

SPR是一种光学传感技术，其核心机制在于金属-介质界面处自由电子的集体振荡（即表面等离子体波SPW）与光纤中的衰减波（EW）之间的耦合效应[28]。

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