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Updated: Aug 23, 2026

Detection of CD40 Protein-Umbelliferone Interaction via Differential Scanning Fluorescence
Published on: March 1, 2024
High sensitivity detection of protein molecules picked up on a probe of atomic force microscope based on the
Takafumi Yamada1, Rehana Afrin, Hideo Arakawa
1Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midoriku, Yokohama 226-8501, Japan.
Abstract:
We developed a method to detect and identify proteins on a probe of the atomic force microscope (AFM) with a high sensitivity. Due to a low background noise of the total internal reflection fluorescence microscope employed as a detecting system, we were able to achieve a high enough sensitivity to detect zeptomole orders of protein molecules immobilized on the tip. Several different methods to immobilize protein molecules to AFM-probes were tested, meant for a wide range of applications of this method. Furthermore, we demonstrated that different proteins were clearly distinguished by immunofluorescence microscopy on the probe using their specific antibodies.
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