Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400716, China.
Nanoscale. 2017 Mar 30;9(13):4593-4600. doi: 10.1039/c6nr09452j.
Imaging of light scattering plasmonic nanoparticles (PNPs) with the aid of the dark-field microscopy imaging (iDFM) technique has attracted wide attention owing to its high signal-to-noise ratio, but to improve the color resolution and contrast of dark-field microscopy (DFM) images of single light scattering PNPs in a small spectral variation environment is still a challenge. In this study, a new color analytical method for resolving the resolution and contrast in DFM images has been developed and further applied for colorimetric analysis using the digital image processing technique. The color of single light scattering PNP images is automatically coded at first with the hue values of the HSI color model, and then amplified using the MATLAB program even for marginal spectral changes, leading to significant improvement of the color resolution of DFM images and easy detection with the naked eye. As a proof of concept, this method is then applied to distinguish single PNPs with various sizes and to visually detect hepatocellular carcinoma-associated microRNA. As it greatly improved the color resolution of iDFM and its detection sensitivity, this method shows promise to serve as a better alternative for sensitive visual analysis and spectrometer-based spectral analysis.
利用暗场显微镜成像（iDFM）技术对光散射等离子体纳米粒子（PNP）进行成像，由于其具有高信噪比而受到广泛关注，但是在小光谱变化环境中提高单个光散射 PNP 的暗场显微镜（DFM）图像的颜色分辨率和对比度仍然是一个挑战。在这项研究中，开发了一种新的颜色分析方法，用于解决 DFM 图像中的分辨率和对比度问题，并进一步应用于使用数字图像处理技术的比色分析。首先，使用 HSI 颜色模型的色调值自动对单个光散射 PNP 图像进行颜色编码，然后使用 MATLAB 程序放大，即使对于边缘光谱变化，也能显著提高 DFM 图像的颜色分辨率，便于肉眼检测。作为概念验证，该方法随后用于区分具有不同尺寸的单个 PNP，并可视化检测肝癌相关 microRNA。由于它大大提高了 iDFM 的颜色分辨率及其检测灵敏度，因此该方法有望成为更敏感的视觉分析和基于光谱仪的光谱分析的更好替代方法。
