Fluorescence emission studies of 4-(2-furylmethylene)-2-phenyl-5-oxazolone embedded in polymer thin film and detection of Fe3+ ion

The photophysical and photochemical properties of azlactone derivative 4-(2-furylmethylene)-2-phenyl-5-oxazolone (PFO) were examined in solvents of tetrahydrofuran (THF), acetonitrile (ACN) and dichloromethane (DCM) and in solid matrix of polyvinyl chloride (PVC). The PFO dye embedded in plasticized PVC matrix has been used in monitoring Fe3+. The PFO dye exhibited satisfactory fluorescence emission based optical response to Fe3+ with a detection limit of 3.8 X 10(-6) M. The sensor composition exhibited a dynamic response to Fe3+ in the concentration range of 6 X 10(-6) -6 X 10(-4) M. The sensor is fully reversible within the dynamic range and the response time (tau(90)) is approximately 2 min under batch conditions. The reproducibility of the sensor membrane was investigated by alternately changing the solution of 2 X 10(-5) M Fe3+ and BES buffer (10(-3) M, pH = 7.0), and relative standard deviation was calculated as 0.4% (n = 7). pH dependence is negligible in the pH range of 4.0-11.0. The cross sensitivity of PFO to Co2+ Ni2+, Zn2+ and CU2+ was also tested and evaluated. (c) 2005 Elsevier Ltd. All rights reserved.