Department of Electricity and Electronics, FCT-ZTF, UPV-EHU, 48080 Bilbao, Spain.
Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 Donostia-Sebastián, Spain.
ACS Sens. 2023 Apr 28;8(4):1827-1834. doi: 10.1021/acssensors.3c00287. Epub 2023 Apr 13.
Spurred by outstanding optical properties, chemical stability, and facile bioconjugation, plasmonic metals have become the first-choice materials for optical signal transducers in biosensing. While the design rules for surface-based plasmonic sensors are well-established and commercialized, there is limited knowledge of the design of sensors based on nanoparticle aggregation. The reason is the lack of control over the interparticle distances, number of nanoparticles per cluster, or multiple mutual orientations during aggregation events, blurring the threshold between positive and negative readout. Here we identify the geometrical parameters (size, shape, and interparticle distance) that allow for maximizing the color difference upon nanoparticle clustering. Finding the optimal structural parameters will provide a fast and reliable means of readout, including unaided eye inspection or computer vision.
受出色的光学性质、化学稳定性和易于生物偶联的推动，等离子体金属已成为生物传感中光信号传感器的首选材料。虽然基于表面的等离子体传感器的设计规则已经成熟并商业化，但基于纳米颗粒聚集的传感器的设计知识有限。原因是在聚集过程中缺乏对颗粒间距离、每个簇中的纳米颗粒数量或多个相互取向的控制，从而模糊了正读和负读之间的界限。在这里，我们确定了允许在纳米颗粒聚集时最大限度地产生颜色差的几何参数（大小、形状和颗粒间距离）。找到最佳结构参数将为快速可靠的读取提供一种手段，包括肉眼检查或计算机视觉。
