A novel polymer inclusion membranes based optode for sensitive determination of Al3+ ions

A novel approach for the determination of Al3+ from aqueous samples was developed using an optode membrane produced by physical inclusion of Al3+ selective reagent, which is morin into a plasticized poly(vinyl chloride). The inclusion of Triton X-100 was found to be valuable and useful for enhancing the sorption of Al3+ ions from liquid phase into the membrane phase, thus increasing the intensity of optode's absorption. The optode showed a linear increase in the absorbance at λmax = 425 nm over the concentration range of 1.85 × 10-6-1.1 × 10-4 mol L-1 (0.05-3 μg mL-1) of Al3+ ions in aqueous solution after 5 min. The limit of detection was determined to be 1.04 × 10-6 mol L-1 (0.028 μg mL-1). The optode developed in the present work was easily prepared and found to be stable, has good mechanical strength, sensitive and reusable. In addition, the optode was tested for Al3+ determination in lake water, river water and pharmaceutical samples, which the result was satisfactory.