Abstract Lysozyme plays an important role in the innate immune system of animal or human body, thus, it is vital to detect it using a high sensitivity and efficiency approach in clinic. Nanostructure-based Surface-enhanced Raman scattering (SERS) substrate is often employed to detect biomolecules. In this study, a nanodots array structure, which was utilized as a micro-nano hybrid SERS substrate, was fabricated using second-scan scratching strategy with AFM-probe. The dependence of the nanodots structure on the machining parameters such as applied normal loads and scratching angles were investigated. The effects of the nanostructure feature sizes and the Au film thickness on the measured SERS spectra that tested using Rhodamine 6G (R6G) were studied. In addition, different drying temperatures and concentrations of NaNO3 solution were used to study the absorption manner of lysozyme on an Ag substrate. The SERS spectra of a binary protein mixture, which includes lysozyme and insulin, were also investigated based on the fabricated nanostructures. Results showed that the substrates fabricated using AFM nanomachining approach may promote the SERS application in biologic field.

中文翻译：

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基于纳米点阵列的溶菌酶吸收方式的无标记表面增强拉曼光谱检测

摘要 溶菌酶在动物或人体的先天免疫系统中发挥着重要作用，因此在临床上采用高灵敏度、高效率的方法对其进行检测至关重要。基于纳米结构的表面增强拉曼散射 (SERS) 基板通常用于检测生物分子。在这项研究中，纳米点阵列结构用作微纳米混合 SERS 衬底，使用带有 AFM 探针的二次扫描刮擦策略制造。研究了纳米点结构对加工参数（例如施加的法向载荷和刮擦角度）的依赖性。研究了纳米结构特征尺寸和 Au 膜厚度对使用罗丹明 6G (R6G) 测试的测量 SERS 光谱的影响。此外，采用不同干燥温度和不同浓度的NaNO3溶液研究溶菌酶在Ag底物上的吸收方式。还基于制造的纳米结构研究了包括溶菌酶和胰岛素的二元蛋白质混合物的 SERS 光谱。结果表明，使用 AFM 纳米加工方法制造的基板可能会促进 SERS 在生物领域的应用。