A fluorescence based endoscopic microcancer detection capsule

Efficient microcancer detection in the small intestine can be realised by infrared fluorescence endoscopy (IRFE), in conjunction with an infrared fluorescent-labeling contrast agent that is designed to be selectively uptaken by cancerous cells. In this paper we present a second generation screening capsule, which is able to measure IR fluorescence levels emitted by the fluorophore indocyanine green (ICG), at different concentrations. The presented mixed-signal system is contained within a compact ingestible capsule, which is however large enough to come into close contact with the intestine walls during peristalsis. In-vitro experiments have shown that the system is able to detect and discriminate low concentrations of ICG, in the nanomolar region, which is required to detect early cancer in the small intestine.