Versatile Near-Infrared Super-Resolution Imaging of Amyloid Fibrils with the Fluorogenic Probe CRANAD-2

Area of Science:

• Biomedical Imaging
• Neuroscience
• Molecular Biology

Background:

• Amyloid aggregates are implicated in neurodegenerative diseases.
• Advanced imaging techniques are crucial for studying these aggregates at the nanoscale.
• Fluorogenic probes are essential for sensitive detection and imaging.

Purpose of the Study:

• To evaluate the performance of CRANAD-2, a fluorogenic curcumin derivative, in super-resolution microscopy.
• To assess CRANAD-2's utility for in vitro and in vivo near-infrared imaging of amyloid aggregates.
• To determine the resolution achievable with CRANAD-2 in stimulated emission depletion (STED) and single-molecule localization microscopy (SMLM).

Main Methods:

• CRANAD-2 was used as a probe for amyloid aggregates.
• Super-resolution imaging techniques, STED and SMLM, were employed.
• Atomic force microscopy (AFM) was used to validate SMLM results.

Main Results:

• CRANAD-2 demonstrated good performance in both STED and SMLM techniques.
• Achieved a resolution in the range of 45-55 nm.
• SMLM-AFM correlation validated the resolution of fine structural features.

Conclusions:

• CRANAD-2 is a versatile and effective probe for nanoscopic imaging of amyloid aggregates.
• Its performance in super-resolution microscopy enables detailed visualization of amyloid structures.
• CRANAD-2 offers a powerful tool for studying neurodegenerative disease mechanisms in vitro and in vivo.