A compact, wireless fluorimeter system for continuous, real-time monitoring of tissue perfusion via in vivo fluorescence signals.

In vivo fluorescence signals provide physiological and pathological insights for the interpretation of biological states associated with anatomical abnormalities or disease. Conventional methods for measuring fluorescence signals rely on bulky, costly instrumentation for imaging or for localized sensing. Here, we report a compact, wireless fluorimeter system for continuous, real-time measurements of the dynamics of fluorescence signals at locations of interest across the body. The approach represents a type of wearable that enables quantitative, interpretable fluorescence readouts and automatic data streaming to standard smart devices. The platform is compatible with injectable fluorescent species of medical relevance, such as indocyanine green, fluorescein, and methylene blue. Measurements from ischemic rodent and healthy porcine models, as well as those associated with limb amputation/replantation studies in rodents, demonstrate physiologically meaningful fluorescence profiles, with validation against ex situ blood analysis. These conceptual and technical advances offer the potential for convenient, continuous monitoring of fluorescence signals to support disease management and long-term patient care.