Optical fiber fluoroprobes in clinical analysis.

We used quartz optical fibers and laser excitation in developing single-fiber fluoroprobes, to be used to measure molecular fluorescence in minute volumes of body fluids. We illustrate and discuss the analytical capabilities of these fluoroprobes. Limits of detection for the anti-tumor drug doxorubicin are about 10(-7) mol/L, by either conventional fluorescence or sequentially excited fluoroscence modes of detection. We also report the results of preliminary in vivo measurements of doxorubicin in the interstitial fluids of human tumors, heterotransplanted in immune-deficient laboratory mice.