Abstract LB-512: A novel rotational Raman imaging device for early cancer detection

Abstract

Abstract A novel Raman imaging device that is capable of rotationally scanning hollow structures has been developed to be used in conjunction with tumor targeting Surface enhanced Raman scattering (SERS) nanoparticles. SERS nanoparticles can act as excellent contrast agents in that they offer ultra high sensitivity, and multiplexing capabilities due to the unique spectral signatures associated with them. One key advantage of multiplexing includes the ability to utilize several targeted SERS probes to target and localize a multitude of unique biomarkers associated with a specific disease, and effectively increasing cancer specificity. The device can potentially be used to distinguish a variety of tissues of interest in the colon such as: flat lesions, varying types of adenomas and carcinomas. There are also applications beyond the colon, such as the esophagus, stomach, oral cavity and bladder. In addition, multiplexing can allow for real-time functional imaging. A 45-degree scanning mirror, actuated with micro-motor, is used to perform circumferential scans of the lumen of the colon at a rate of 1 revolution per second and a spatial resolution or approximately 1.5 mm. The device is able to be used with currently available endoscopes by inserting it into the working channel of an endoscope. The use of many (36) multi-mode fibers is used to increase the flexibility of the fiber bundle so that it can be inserted and used in a fully articulating endoscope while still being able to collect a sufficient amount scattered Raman light. When in the circumferential scanning mode, American National Standards Institute (ANSI) regulations will allow us to increase the laser illumination power to about 580 mW at a scan rate of 60rpm, resulting in a detection limit of approximately 1 pM of SERS nanoparticles. One of the key features of our Raman device is that it has been designed for efficient use over a wide range of working distances. This is necessary to accommodate for imperfect centering of the device within the colon, as well as variable working distances due to folds and bends within the colon. These techniques could allow endoscopists to distinguish between normal and cancerous tissues instantly, as well as to identify flat lesions that are easily missed during conventional screening endoscopy. After a suspicious region has been identified, the rotating mirror can be held at a certain angle, and used to help guide biopsies or resection of tissues in real-time. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr LB-512. doi:1538-7445.AM2012-LB-512