Dallari Caterina, Capitini Claudia, Calamai Martino, Trabocchi Andrea, Pavone Francesco Saverio, Credi Caterina
European Laboratory for non-linear Spectroscopy (LENS), University of Florence, 50019 Sesto Fiorentino, Florence, Italy.
Department of Physics, University of Florence, 50019 Sesto Fiorentino, Florence, Italy.
Nanomaterials (Basel). 2021 Mar 8;11(3):665. doi: 10.3390/nano11030665.
Gold nanoparticles (AuNPs) show physicochemical and optical functionalities that are of great interest for spectroscopy-based detection techniques, and especially for surface enhanced Raman spectroscopy (SERS), which is capable of providing detailed information on the molecular content of analysed samples. Moreover, the introduction of different moieties combines the interesting plasmonic properties of the AuNPs with the specific and selective recognition capabilities of the antibodies (Ab) towards antigens. The conjugation of biomolecules to gold nanoparticles (AuNPs) has received considerable attention for analysis of liquid samples and in particular biological fluids (biofluids) in clinical diagnostic and therapeutic field. To date, gold nanostars (AuNSts) are gaining more and more attention as optimal enhancers for SERS signals due to the presence of sharp branches protruding from the core, providing a huge number of "hot spots". To this end, we focused our attention on the design, optimization, and deep characterization of a bottom up-process for (i) AuNPs increasing stabilization in high ionic strength buffer, (ii) covalent conjugation with antibodies, while (iii) retaining the biofunctionality to specific tag analyte within the biofluids. In this work, a SERS-based substrate was developed for the recognition of a short fragment (HA) of the hemagglutinin protein, which is the major viral antigen inducing a neutralizing antibody response. The activity and specific targeting with high selectivity of the Ab-AuNPs was successfully tested in transfected neuroblastoma cells cultures. Then, SERS capabilities were assessed measuring Raman spectra of HA solution, thus opening interesting perspective for the development of novel versatile highly sensitive biofluids sensors.
金纳米颗粒（AuNPs）展现出物理化学和光学功能，这些功能对于基于光谱的检测技术，特别是对于表面增强拉曼光谱（SERS）极具吸引力，SERS能够提供有关分析样品分子含量的详细信息。此外，引入不同的部分将AuNPs有趣的等离子体特性与抗体（Ab）对抗原的特异性和选择性识别能力结合起来。生物分子与金纳米颗粒（AuNPs）的共轭在临床诊断和治疗领域的液体样品分析，特别是生物流体（生物体液）分析中受到了广泛关注。迄今为止，由于从核心伸出尖锐分支，提供大量“热点”，金纳米星（AuNSts）作为SERS信号的最佳增强剂越来越受到关注。为此，我们将注意力集中在一种自下而上的过程的设计、优化和深入表征上，该过程用于（i）提高AuNPs在高离子强度缓冲液中的稳定性，（ii）与抗体进行共价共轭，同时（iii）在生物体液中保留对特定标记分析物的生物功能。在这项工作中，开发了一种基于SERS的底物，用于识别血凝素蛋白的短片段（HA），HA是诱导中和抗体反应的主要病毒抗原。在转染的神经母细胞瘤细胞培养物中成功测试了Ab-AuNPs的活性和高选择性特异性靶向。然后，通过测量HA溶液的拉曼光谱评估了SERS能力，从而为新型通用高灵敏度生物流体传感器的开发开辟了有趣的前景。
