Department of Biomedical Engineering, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.
Light, Nanomaterials & Nanotechnologies (L2n), CNRS-UMR 7076, University of Technology of Troyes, 10000, Troyes, France.
Analyst. 2024 May 13;149(10):3017-3025. doi: 10.1039/d4an00194j.
Tumor necrosis factor-alpha (TNF-α) serves as a crucial biomarker in various diseases, necessitating sensitive detection methodologies. This study introduces an innovative approach utilizing an aptamer-functionalized surface plasmon resonance (SPR) substrate together with an ultrasensitive measure, the Goos-Hänchen (GH) shift, to achieve sensitive detection of TNF-α. The developed GH-aptasensing platform has shown a commendable figure-of-merit of 1.5 × 10 μm per RIU, showcasing a maximum detectable lateral position shift of 184.7 ± 1.2 μm, as characterized by the glycerol measurement. Employing aptamers as the recognition unit, the system exhibits remarkable biomolecule detection capabilities, including the experimentally obtained detection limit of 1 aM for the model protein bovine serum albumin (BSA), spanning wide dynamic ranges. Furthermore, the system successfully detects TNF-α, a small cytokine, with an experimental detection limit of 1 fM, comparable to conventional SPR immunoassays. This achievement represents one of the lowest experimentally derived detection limits for cytokines in aptamer-based SPR sensing. Additionally, the application of the GH shift marks a ground breaking advancement in aptamer-based biosensing, holding significant promise for pushing detection limits further, especially for small cytokine targets.
肿瘤坏死因子-α（TNF-α）作为各种疾病的重要生物标志物，需要灵敏的检测方法。本研究介绍了一种利用适体功能化的表面等离子体共振（SPR）基底和超灵敏的古斯-汉欣（GH）位移的创新方法，实现了 TNF-α的灵敏检测。所开发的 GH-适体传感平台具有令人称赞的每 RIU 1.5×10μm 的品质因数，最大可检测的横向位置位移为 184.7±1.2μm，这是通过甘油测量得出的。该系统采用适体作为识别单元，具有出色的生物分子检测能力，包括实验获得的模型蛋白牛血清白蛋白（BSA）的检测限为 1aM，具有较宽的动态范围。此外，该系统成功检测到了小细胞因子 TNF-α，实验检测限为 1fM，与传统的 SPR 免疫分析相当。这一结果是基于适体的 SPR 传感中细胞因子的最低实验检测限之一。此外，GH 位移的应用标志着基于适体的生物传感的一项突破性进展，有望进一步推动检测限的提高，特别是对于小细胞因子靶标。
