Nanoencapsulated fluorescence indicator molecules measuring pH and pO2 down to submicroscopical regions in the basis...

To measure pO2 in gases or fluids and pH in solutions the fluorescence indicators pyrene butyric acid and beta-methylumbelliferone, respectively, were nanoencapsulated to obtain nano-probes for measurement in physiological structures of nano-range. For pH the fluorescence changes of beta-methylumbelliferone were monitored, for pO2 the fluoresence quenching of pyrene butyric acid by oxygen were registered. Drawing log (S1/S2) versus pH, one obtains a straight line between the pH from 6 to 8. A linear increase in pO2 between 0 and 400 torr yields a linear increase in the reciprocal fluorescence signal.