In this work, multimodal two-photon excitation fluorescence (TPEF) and third-harmonic generation (THG) microscopy is used together with second-harmonic generation (SHG) to image gold standard hematoxylin and eosin histology slides. The nonlinear responses were investigated for hematoxylin and eosin stains. It is shown that the extracellular matrix (ECM) can be visualized using THG image contrast. THG signal is typically associated with interfaces and nanostructures where abrupt changes in the refractive index takes place, e.g. at blood vessel walls as well as the dense nuclei. Polarimetric THG provides a new method for ultrastructural ECM visualization. The ability of THG microscopy to visualize simultaneously nuclei and ECM is exemplified by imaging clinical tissue samples. THG turned out to be an excellent counterstaining contrast to SHG that reveals ECM proteins, cells and cell nuclei, which can be utilized for studying interactions between cells and ECM. Multiphoton imaging can be applied for investigation of structural changes in connective tissue due to various diseases and is beneficial in observing ECM and cell nuclei in cancer diagnostics and prognostics.
We investigate the chiral response of type I collagen using polarimetric second harmonic generation (SHG) microscopy. By flipping the sample, we observe changes in the sign of the amplitude of the chiral susceptibility ratio (C), while its retardancy phase with respect to the achiral ratio (R) remains unchanged. Our findings suggest that the chiral response of collagen originates from the interaction between electric dipole moments and laser radiation. This study demonstrates the potential of polarimetric SHG microscopy for studying collagen properties and visualizing disease-related alterations.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.