State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University , Guangzhou 510275, China.
ACS Nano. 2016 Jun 28;10(6):5800-8. doi: 10.1021/acsnano.5b08081. Epub 2016 May 12.
In advanced nanoscience, there is a strong desire to trap and detect nanoscale objects with high-throughput, single-nanoparticle resolution and high selectivity. Although emerging optical methods have enabled the selective trapping and detection of multiple micrometer-sized objects, it remains a great challenge to extend this functionality to the nanoscale. Here, we report an approach to trap and detect nanoparticles and subwavelength cells at low optical power using a parallel photonic nanojet array produced by assembling microlenses on an optical fiber probe. Benefiting from the subwavelength confinement of the photonic nanojets, tens to hundreds of nanotraps were formed in three dimensions. Backscattering signals were detected in real time with single-nanoparticle resolution and enhancement factors of 10(3)-10(4). Selective trapping of nanoparticles and cells from a particle mixture or human blood solution was demonstrated using the nanojet array. The developed nanojet array is potentially a powerful tool for nanoparticle assembly, biosensing, single-cell analysis, and optical sorting.
在先进的纳米科学中，人们强烈希望能够以高通量、单纳米颗粒分辨率和高选择性来捕获和检测纳米级物体。尽管新兴的光学方法已经能够实现对多个微米级物体的选择性捕获和检测，但将这种功能扩展到纳米级仍然是一个巨大的挑战。在这里，我们报告了一种使用组装在光纤探针上的微透镜来产生平行光子纳米射流阵列的方法，以低光功率捕获和检测纳米颗粒和亚波长细胞。受益于光子纳米射流的亚波长限制，在三维空间中形成了数十到数百个纳米陷阱。利用单纳米颗粒分辨率和增强因子为 10(3)-10(4)，实时检测背向散射信号。使用纳米射流阵列可以从粒子混合物或人血溶液中选择性地捕获纳米颗粒和细胞。所开发的纳米射流阵列有望成为纳米颗粒组装、生物传感、单细胞分析和光分选的强大工具。
