Dynamically Monitoring pH in Living Organisms Based on a SERS‐Active Optical Fiber

Abstract

Abstract To dynamically monitor pH in living organisms, a pH‐sensitive surface‐enhanced Raman scattering (SERS)‐active optical fiber is designed and developed. A 2‐cm‐long optical fiber is processed with an inclined end to facilitate entering the body of the optical fiber, and a hole is etched near the inclined end to integrate pH‐sensitive SERS probes and protect them from being erased during entering the body. The pH‐sensitive SERS probes in the hole respond thoroughly to the buffer environment in 5 min and the body environment in 15 min, respectively. The fabricated SERS‐active optical fiber is used to dynamically monitor the change in pH in tissues of living rats, such as muscle and brain. The SERS‐active optical fibers will be a versatile platform to integrate optical probes such as SERS probes and fluorescence probes to dynamically monitor life activities in living organisms.