A transparent waveguide chip for versatile total internal reflection fluorescence-based microscopy and nanoscopy

Abstract

Total internal reflection fluorescence (TIRF) microscopy is an imaging technique that, in comparison to confocal microscopy, does not require a trade-off between resolution, speed, and photodamage. Here, we introduce a waveguide platform for chip-based TIRF imaging based on a transparent substrate, which is fully compatible with sample handling and imaging procedures commonly used with a standard #1.5 glass coverslip. The platform is fabricated using standard complementary metal-oxide-semiconductor techniques which can easily be scaled up for mass production. We demonstrate its performance on synthetic and biological samples using both upright and inverted microscopes, and show how it can be extended to super-resolution applications, achieving a resolution of 116 nm using super resolution radial fluctuations. These transparent chips retain the scalable field of view of opaque chip-based TIRF and the high axial resolution of TIRF, and have the versatility to be used with many different objective lenses, microscopy methods, and handling techniques. We see this as a technology primed for widespread adoption, increasing both TIRF’s accessibility to users and the range of applications that can benefit from it.

SNC‐TIRS: Label‐Free Single Nanoparticle Characterization System Based on Total Internal Reflection Scattering Signal

“…cTIRF further offers advantages similar to those of chip‐based TIRF systems such as: i) efficient segregation of scattered light from excitation light due to placement of excitation optics perpendicular to the emission path, ii) compatibility with different numerical aperture objectives. [ 34 ] Additionally, employing a TIR mode of illumination to generate evanescent wave‐based scattering signal from sample nanoparticles results in the elimination of out‐of‐focus light and hence, improved signal‐to‐noise ratios. [ 34 ] Furthermore, there is no requirement of a labeling step such as in fluorescence‐based experiments.…”

Chip-based multimodal super-resolution microscopy for histological investigations of cryopreserved tissue sections

“…The process pressure (2.3 × 10 −4 Torr), beam voltage (500 V), beam current (100 mA), radiofrequency power (500 W), and substrate temperature (15 °C) were kept constant. Finally, the wafers were placed in a three-zone semiconductor furnace at 600 °C in an oxygen environment for 3 h (in batch) to reduce the stress and supplement the oxygen deficiency created in Ta 2 O 5 during the sputtering and the etching process 31 .…”

“…Among the existing histological methods, we chose the Tokuyasu protocol 30 for the preparation of the tissue sections. This cryosectioning method provides excellent ultrastructural preservation, high molecular antigenicity, and a thin section thickness (70 nm to 1 µm) that assists both in reducing the light scattering artifacts associated with thicker samples 31 and in making optimal use of the illumination delivered by the photonic chip. We describe the staining protocols and the imaging parameters necessary for photonic chip-based microscopy of tissue samples and discuss the challenges and the advantages offered by this imaging platform for the investigation of tissue sections.…”

Optical properties and complex refractive index of Co doped ZnO waveguide thin films elaborated by spray pyrolysis

“…Optical fibers are relatively flexible and immune to electromagnetic interference so they found use in communications. Transparent thin films waveguides are of high quality, controllable and efficient and by that, they had been employed as bio and chemical sensors [1][2][3], integrated optical amplifier [4] and a guided layer in total internal reflection fluorescence microscope [5] to name a few. A dielectric waveguide can be defined as any structure used to control the flow of electromagnetic waves in a certain direction.…”