We demonstrate a multi-spectral scanning fiber endoscope (SFE) that collects fluorescence images in vivo from
three target peptides that bind specifically to murine colonic adenomas. This ultrathin endoscope was demonstrated
in a genetically engineered mouse model of spontaneous colorectal adenomas based on somatic Apc (adenomatous
polyposis coli) gene inactivation. The SFE delivers excitation at 440, 532, 635 nm with <2 mW per channel. The
target 7-mer peptides were conjugated to visible organic dyes, including 7-Diethylaminocoumarin-3-carboxylic acid
(DEAC) (λex=432 nm, λem=472 nm), 5-Carboxytetramethylrhodamine (5-TAMRA) (λex=535 nm, λem=568 nm), and
CF-633 (λex=633 nm, λem=650 nm). Target peptides were first validated using techniques of pfu counting, flow
cytometry and previously established methods of fluorescence endoscopy. Peptides were applied individually or in
combination and detected with fluorescence imaging. The ability to image multiple channels of fluorescence
concurrently was successful for all three channels in vitro, while two channels were resolved simultaneously in vivo.
Selective binding of the peptide was evident to adenomas and not to adjacent normal-appearing mucosa. Multispectral
wide-field fluorescence detection using the SFE is achievable, and this technology has potential to advance
early cancer detection and image-guided therapy in human patients by simultaneously visualizing multiple over
expressed molecular targets unique to dysplasia.