Gayathri R, Suchand Sandeep C S, Gummaluri V S, Asik R Mohamed, Padmanabhan Parasuraman, Gulyás Balázs, Vijayan C, Murukeshan V M
Centre for Optical and Laser Engineering (COLE), School of Mechanical and Aerospace Engineering, Nanyang Technological University 50 Nanyang Avenue 639798 Singapore
Department of Physics, Indian Institute of Technology Madras Chennai 600036 India
Nanoscale Adv. 2022 Apr 1;4(10):2278-2287. doi: 10.1039/d1na00866h. eCollection 2022 May 17.
Narrow bandwidth, high brightness, and spectral tunability are the unique properties of lasers that make them extremely desirable for fluorescence imaging applications. However, due to the high spatial coherence, conventional lasers are often incompatible for wide-field fluorescence imaging. The presence of parasitic artefacts under coherent illumination causes uneven excitation of fluorophores, which has a critical impact on the reliability, resolution, and efficiency of fluorescence imaging. Here, we demonstrate artefact-free wide-field fluorescence imaging with a bright and low threshold silver nanorod based plasmonic random laser, offering the capability to image finer cellular features with sub-micrometer resolution even in highly diffusive biological samples. A spatial resolution of 454 nm and up to 23% enhancement in the image contrast in comparison to conventional laser illumination are attained. Based on the results presented in this paper, random lasers, with their laser-like properties and spatial incoherence are envisioned to be the next-generation sources for developing highly efficient wide-field fluorescence imaging systems having high spatial and temporal resolution for real-time, bioimaging.
窄带宽、高亮度和光谱可调性是激光的独特特性，这些特性使得激光在荧光成像应用中极具吸引力。然而，由于高空间相干性，传统激光通常不适用于宽场荧光成像。相干照明下寄生伪像的存在会导致荧光团激发不均匀，这对荧光成像的可靠性、分辨率和效率有至关重要的影响。在此，我们展示了使用基于亮且低阈值银纳米棒的等离子体随机激光进行无伪像宽场荧光成像，即使在高度散射的生物样本中也能够以亚微米分辨率成像更精细的细胞特征。与传统激光照明相比，实现了454 nm的空间分辨率以及高达23%的图像对比度增强。基于本文给出的结果，具有类似激光特性和空间非相干性的随机激光有望成为下一代光源，用于开发具有高空间和时间分辨率的高效宽场荧光成像系统，以进行实时生物成像。
