Continuous monitoring of adriamycin in vivo using fiber optic-based fluorescence chemical sensor

A novel method using a fiber optic-based fluorescence chemical sensor (FOCS) was developed for the preparation of on-line continuous monitoring of a drug in animals. First, an accurate optical design was used to enhance the intensity of light from a 100-microm optic fiber so the fluorescence signal can be detected. Second, A new sol-gel method was used to fix the fluorescence substance 4-(N,N-dioctyl)amino-7-nitrobenz-2-oxa-1,3-diazole (D-70) on the tip of the fiber. The variation in the quenching means variation in the concentration of Adriamycin (ADM) in rabbit's blood. ADM is determined by FOCS based on fluorescence multiple quenching. In a simple animal model, the carotid artery was catheterized with a cannula, housing a 100-microm optic fiber. The average recovery of all the tested compounds within the set concentration range was 99.4-106.2%; the within-day and between-day repeatability values were acceptable between 6.6-11.4% and 5.9-11.7%. The method permitted detection limits as low as 0.057 microg x mL(-1) at a signal-to-noise ratio of 3. The fiber optic chemical sensor is potentially useful for monitoring blood concentrations of drugs and metabilities in the biomedical field.