Key Laboratory of Biomaterials of Guangdong Higher Education Institutes, Department of Biomedical Engineering, Jinan University, Guangzhou 510632, China.
Molecules. 2022 Nov 16;27(22):7918. doi: 10.3390/molecules27227918.
The accurate and sensitive detection of biomolecules by surface-enhanced Raman spectroscopy (SERS) is possible, but remains challenging due to the interference from biomolecules in complex samples. Herein, a new SERS sensor is developed for background-free detection of hydrogen peroxide (HO) with an ultralow detection limit (1 × 10 mol/L), using a Raman-silent strategy. The Au microparticles (Au-RSMPs) resembling rose-stones are devised as SERS substrates with a high enhancement effect, and 4-mercaptophenylboronic acid (4-MPBA) is selected as an HO-responsive Raman reporter. Upon the reaction with HO, the phenylboronic group of 4-MPBA was converted to a phenol group, which subsequently reacted with 4-diazonium-phenylalkyne (4-DP), an alkyne-carrying molecule via the azo reaction. The formed product exhibits an intense and sharp SERS signal in the Raman-silent region, avoiding interference of impurities and biomolecules. As a proof-of-concept demonstration, we show that this SERS sensor possesses significant merits towards the determination of HO in terms of broad linear range, low limit of detection, and high selectivity, showing promise for the quantitative analysis of HO in complicated biological samples.
通过表面增强拉曼光谱（SERS）可以实现对生物分子的准确、灵敏检测，但由于复杂样品中生物分子的干扰，这仍然具有挑战性。在此，我们开发了一种新的 SERS 传感器，采用拉曼静默策略，用于无背景检测过氧化氢（HO），具有超低的检测限（1×10-6mol/L）。设计了类似于玫瑰石的 Au 微米颗粒（Au-RSMPs）作为 SERS 基底，具有高增强效应，选择 4-巯基苯硼酸（4-MPBA）作为 HO 响应的拉曼报告分子。与 HO 反应后，4-MPBA 的苯硼酸基团被转化为苯酚基团，随后通过偶氮反应与携带炔基的分子 4-二氮苯基-1-丙炔（4-DP）反应。形成的产物在拉曼静默区域表现出强烈而尖锐的 SERS 信号，避免了杂质和生物分子的干扰。作为概念验证的演示，我们表明该 SERS 传感器在 HO 的测定方面具有显著的优点，具有较宽的线性范围、低检测限和高选择性，有望用于复杂生物样品中 HO 的定量分析。
