Highly sensitive fluorescence optode for aluminium(III) based on non-plasticized polymer inclusion membrane

A highly sensitive and simple reagent immobilization procedure for a non-plasticized fluorescence optode based on polymer inclusion membranes (PIM) has been developed. The preparation procedure is based on physical immobilization procedure, namely encapsulation technique which produces an optical sensing membrane. The sensitive PIM contains poly (vinyl chloride) (PVC) as the base polymer, Aliquat 336 as an extractant and sodium morin-5-sulphonate (NaMSA) as the reagent. The use of PIM has increased the response of the PIM based optode about five-fold enhancement compared to the non-PIM optode. The optimized optode was characterized by a linear calibration curve in the range from 5.19 x 10(-7) to 6.00 x 10(-5) mol L-1 of aluminium(III) (Al(III)), with a detection limit of 4.07 x 10-7 mol L-1. The response of the optode was three minutes and it was also found to be reproducible. The optode has been successfully tested for the determination of Al(III) in natural water samples and result obtained is comparable to atomic absorption spectrometry method. (C) 2014 Elsevier B.V. All rights reserved.