Translator Disclaimer
10 December 1996 Scanning near-field optical/atomic-force microscopy for biomedical applications
Author Affiliations +
We have developed scanning near-field optical/atomic force microscopy (SNOM/AFM). The SNOM/AFM uses a bent optical fiber simultaneously as a dynamic force AFM cantilever and a SNOM probe. Resonant frequency of the optical fiber cantilever is 15 - 40 kHz. Optical resolution of the SNOM/AFM images shows less than 50 nm. The SNOM/AFM system contains photon counting system and polychrometer/ICCD system to observe fluorescence image and spectrograph of micro areas, respectively. A SNOM-AFM system was newly applied to analyses of biological samples. In this system a feedback signal from AFM in the noncontact mode was used to scan the probe tip along the surface contour of the sample. An optical fiber with a sharp tip on one end was bent for use as cantilever, and ac amplitude of the cantilever deflection was held constant during scanning by moving the stage. Green fluorescent protein (GFP) absorbs blue light and emits green light. GFP should be a convenient indicator of transformation and one that could allow cells to be separated with fluorescence-activated cell sorting. The gene coding to GFP was cloned in recombinant E.coli and plant cells. Spatial distribution of GFP gene expression was clarified using a SNOM-AFM system. Fluorescent spectroscopic analyses supported GFP was surely produced in E.coli and plant cells. Applications to gene identification in human genomes were also discussed.
© (1996) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Eiichi Tamiya, Shinichiro Iwabuchi, Yuji Murakami, Toshifumi Sakaguchi, Kenji Yokoyama, Norio Chiba, and Hiroshi Muramatsu "Scanning near-field optical/atomic-force microscopy for biomedical applications", Proc. SPIE 2836, Chemical, Biochemical, and Environmental Fiber Sensors VIII, (10 December 1996);

Back to Top