Surface-enhanced Raman scattering (SERS) nanotags have been extensively studied for targets detection. However, achieving accurate detection of specific targets often requires the functionalization of SERS nanostructures with various biological components like antibodies, nucleic acid aptamers, or peptides. This process is intricate and involves introducing different functional groups on the protective shell layer, which may result in SERS nanotags aggregation, reduced biorecognition element activity, and chaotic orientation on the surface. In this study, we devised spherical peptide nanoparticles with both recognition and anchoring functions through the self-assembly of TFF and CFF peptides, presenting a versatile strategy for SERS nanotag functionalization. The exposed cysteine residues and T sequences (served as the target-specific recognition sequence) after self-assembly, demonstrated binding to gold SERS nanostructure and recognition of specific targets, respectively. We showcase the high sensitivity and specificity of this method by detecting the liver fibrosis marker LECT2. The method was highly sensitive for the detection of LECT2 with an LOD of 0.0015 ng/mL. The method's adaptability is underscored by the ease of adjusting the sequence within the T portion, suggesting its potential generalization for the efficient detection of various targets.

中文翻译：

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生物传感中通用的自组装肽纳米颗粒耦合 SERS 标签

表面增强拉曼散射（SERS）纳米标签已被广泛研究用于目标检测。然而，实现对特定目标的准确检测通常需要使用抗体、核酸适体或肽等各种生物成分对 SERS 纳米结构进行功能化。这个过程非常复杂，涉及在保护壳层上引入不同的官能团，这可能会导致SERS纳米标签聚集、生物识别元件活性降低以及表面取向混乱。在这项研究中，我们通过TFF和CFF肽的自组装设计了具有识别和锚定功能的球形肽纳米粒子，提出了SERS纳米标签功能化的通用策略。自组装后暴露的半胱氨酸残基和T序列（作为目标特异性识别序列）分别证明了与金SERS纳米结构的结合和对特定目标的识别。我们通过检测肝纤维化标志物 LECT2 展示了该方法的高灵敏度和特异性。该方法对 LECT2 的检测高度敏感，LOD 为 0.0015 ng/mL。该方法的适应性通过易于调整 T 部分内的序列而得到强调，表明其对于有效检测各种目标的潜在推广。