Abstract
Fluorescence microscopy in the second near-infrared optical window (NIR-II, 1000–1350 nm) has become a technique of choice for non-invasive in vivo imaging. The deep penetration of NIR light in living tissue, as well as negligible tissue autofluorescence within this optical range, offers increased resolution and contrast with even greater penetration depths. Here, we present a custom-built spinning-disc confocal laser microscope (SDCLM) that is specific to imaging in the NIR-II. The SDCLM achieves a lateral resolution of 0.5 ± 0.1 µm and an axial resolution of 0.6 ± 0.1 µm, showing a ~17% and ~45% enhancement in lateral and axial resolution, respectively, compared to the corresponding wide-field configuration. We furthermore showcase several applications that demonstrate the use of the SDCLM for in situ, spatiotemporal tracking of NIR particles and bioanalytes within both synthetic and biological systems.
Highlights
A variety of near-infrared (NIR) fluorophores, such as single-walled carbon nanotubes (SWCNTs), quantum dots (QDs), inorganic nanoparticles, fluorescent proteins, and dyes, have been developed for imaging and optical sensing applications[1,2,3,4,5,6,7]
An alternative approach is spinning-disc confocal light microscopy (SDCLM), which is a high-speed optical sectioning technique widely used in biological sciences[21]
Whereas existing commercially available setups are largely limited to confocal fluorescence imaging in the visible region of the optical spectrum, this manuscript presents a spinning-disc confocal setup tailored for imaging in the NIR-II window
Summary
A variety of near-infrared (NIR) fluorophores, such as single-walled carbon nanotubes (SWCNTs), quantum dots (QDs), inorganic nanoparticles, fluorescent proteins, and dyes, have been developed for imaging and optical sensing applications[1,2,3,4,5,6,7]. Recent advancements in wide-field deconvolution, laser-scanning confocal and super-resolution microscopy offer promising approaches to achieving high-resolution images of NIR-II fluorophores[17,18,19,20] These methods require relatively long acquisition times that limit their use for real-time monitoring[19]. The advantages of NIR SDCLM imaging is exemplarily demonstrated in three distinct applications: single-particle tracking of NIR fluorescent nanoparticles in solution, spatial distribution of internalized nanoparticles within an organelle, and optical detection of glucose using immobilized SWCNT-based sensors
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
