García-Ramírez Josué Ismael, Luna-Cervantes Marcos, Izaguirre-Hernández Irma Yadira, Hernández-Torres Julián, Juárez-Aguilar Enrique, Thomas-Dupont Pablo, Remes-Troche José María, Zamora-Peredo Luis
Centro de Investigación en Micro y Nanotecnología, Universidad Veracruzana, Boca del Río 94294, Mexico.
Facultad de Bioanálisis, Universidad Veracruzana, Veracruz 91700, Mexico.
Biosensors (Basel). 2025 Sep 22;15(9):632. doi: 10.3390/bios15090632.
Spiky Au-Ag nanostars offer intense plasmonic enhancement due to their sharp-tipped morphology, enabling powerful surface-enhanced Raman scattering (SERS). Here, we report a liquid-phase SERS platform that addresses current limitations in cancer biomarker detection, such as low sensitivity and dependence on Raman reporters. Nanostar concentration was tuned by simple centrifugation (10, 30, and 60 min), and their SERS performance was evaluated using methylene blue (MB) and mercaptopropionic acid (MPA) as probe molecules. Signal intensity scaled with nanostar content, enabling sensitive detection. Optimized nanostars were functionalized with MPA, 1-Ethyl-3-(3-dimethylamino1-Ethyl-3-(3dimethylaminopropyl1) carbodiimide (EDC), and N-Hydroxy succinimide (NHS) for covalent attachment of monoclonal anti-α-fetoprotein antibodies (AFP-Ab), facilitating the detection of AFP antigens across 167-38 ng/mL (antibody) and 500-0 ng/mL (antigen) ranges. The limit of detection (LOD) for the antigens was determined to be 16.73 ng/mL. Unlike conventional SERS systems, this aqueous, surfactant-free platform exploits the intrinsic vibrational modes of AFP, enabling sensitive and rapid biomarker detection with strong potential for early cancer diagnostics.
尖刺状金-银纳米星因其尖锐的形态提供了强烈的等离子体增强效应，从而实现了强大的表面增强拉曼散射（SERS）。在此，我们报道了一种液相SERS平台，该平台解决了当前癌症生物标志物检测中的局限性，如灵敏度低和对拉曼报告分子的依赖性。通过简单离心（10、30和60分钟）来调节纳米星浓度，并使用亚甲基蓝（MB）和巯基丙酸（MPA）作为探针分子评估其SERS性能。信号强度与纳米星含量成比例，实现了灵敏检测。用MPA、1-乙基-3-（3-二甲基氨基丙基）碳二亚胺（EDC）和N-羟基琥珀酰亚胺（NHS）对优化后的纳米星进行功能化，用于单克隆抗甲胎蛋白抗体（AFP-Ab）的共价连接，便于在167-38 ng/mL（抗体）和500-0 ng/mL（抗原）范围内检测AFP抗原。抗原的检测限确定为16.73 ng/mL。与传统的SERS系统不同，这个无表面活性剂的水性平台利用了AFP的固有振动模式，具有灵敏、快速检测生物标志物的能力，在早期癌症诊断方面具有巨大潜力。
