Simple dip-probe fluorescence setup sensor for in situ environmental determinations

A novel fluorescence dip-probe POF (Polymer Optical Fiber) sensor that allows performing in situ chemical determinations has been fabricated. The dip-probe sensor design has been optimized by simulations in order to improve the fluorescence collection. To demonstrate its possibilities, it has been chemically activated with a lead-selective plasticized PVC (polyvinylchloride) membrane containing a new synthesized suitable fluoroionophore and a commercial lead ionophore. The analytical response of the dip-probe sensor has been characterized and it shows a fully reversible response with a sensitivity of -35.10 mV/dec C and a Pb2+ detection limit of 7 × 10-6 M, which can be appropriate for monitoring contamination episodes. No significant interferences with other metal ions have been found. The device has been finally tested to determine the lead content in contaminated natural samples with promising results. © 2009 Elsevier B.V. All rights reserved.