当前位置: X-MOL 学术ACS Photonics › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Background-Suppressed High-Throughput Mid-Infrared Photothermal Microscopy via Pupil Engineering
ACS Photonics ( IF 6.5 ) Pub Date : 2021-10-14 , DOI: 10.1021/acsphotonics.1c01197
Haonan Zong 1 , Celalettin Yurdakul 1 , Yeran Bai 1 , Meng Zhang 2 , M Selim Ünlü 3 , Ji-Xin Cheng 3
Affiliation  

Mid-infrared photothermal (MIP) microscopy has been a promising label-free chemical imaging technique for functional characterization of specimens owing to its enhanced spatial resolution and high specificity. Recently developed wide-field MIP imaging modalities have drastically improved speed and enabled high-throughput imaging of micron-scale subjects. However, the weakly scattered signal from subwavelength particles becomes indistinguishable from the shot-noise as a consequence of the strong background light, leading to limited sensitivity. Here, we demonstrate background-suppressed chemical fingerprinting at a single nanoparticle level by selectively attenuating the reflected light through pupil engineering in the collection path. Our technique provides over 3 orders of magnitude background suppression by quasi-darkfield illumination in the epi-configuration without sacrificing lateral resolution. We demonstrate 6-fold signal-to-background noise ratio improvement, allowing for simultaneous detection and discrimination of hundreds of nanoparticles across a field of view of 70 μm × 70 μm. A comprehensive theoretical framework for photothermal image formation is provided and experimentally validated with 300 and 500 nm PMMA beads. The versatility and utility of our technique are demonstrated via hyperspectral dark-field MIP imaging of S. aureus and E. coli bacteria and MIP imaging of subcellular lipid droplets inside C. albicans and cancer cells.

中文翻译:

通过瞳孔工程进行背景抑制的高通量中红外光热显微镜

由于其增强的空间分辨率和高特异性,中红外光热 (MIP) 显微镜已成为一种有前途的无标记化学成像技术,可用于标本的功能表征。最近开发的广域 MIP 成像模式极大地提高了速度,并实现了微米级对象的高通量成像。然而,由于强背景光,来自亚波长粒子的弱散射信号与散粒噪声无法区分,导致灵敏度受限。在这里,我们通过在收集路径中通过瞳孔工程选择性地衰减反射光,在单个纳米粒子水平上展示了背景抑制的化学指纹。我们的技术通过外延配置中的准暗场照明提供超过 3 个数量级的背景抑制,而不会牺牲横向分辨率。我们展示了 6 倍的信噪比改进,允许在 70 μm × 70 μm 的视场内同时检测和区分数百个纳米粒子。提供了光热图像形成的综合理论框架,并使用 300 和 500 nm PMMA 珠进行了实验验证。通过高光谱暗场 MIP 成像证明了我们技术的多功能性和实用性 允许在 70 μm × 70 μm 的视野中同时检测和区分数百个纳米颗粒。提供了光热图像形成的综合理论框架,并使用 300 和 500 nm PMMA 珠进行了实验验证。通过高光谱暗场 MIP 成像证明了我们技术的多功能性和实用性 允许在 70 μm × 70 μm 的视野中同时检测和区分数百个纳米颗粒。提供了光热图像形成的综合理论框架,并使用 300 和 500 nm PMMA 珠进行了实验验证。通过高光谱暗场 MIP 成像证明了我们技术的多功能性和实用性金黄色葡萄球菌大肠杆菌细菌以及白色念珠菌和癌细胞内亚细胞脂滴的 MIP 成像。
更新日期:2021-11-17
down
wechat
bug