Fabrication of a luminescent chemosensor for selective detection of Al 3+ used as an adjuvant in pharmaceutical drugs.

A new fluorescent chemosensor (NAN), fabricated by integrating 2-hydroxy naphthaldehyde and 1,8-naphthalic anhydride, shows high affinity for aluminium over other bio-relevant metal ions. The probe solution rapidly switched from non-fluorescent to bright blue fluorescence upon the addition of Al 3+ under a UV-lamp, possessing a remarkably low detection limit of 33 nM. The interaction mechanism between the metal ion and NAN has been well established by a number of techniques such as absorbance, fluorescence, and 1 H NMR titration and verified by detailed theoretical calculations as well. To show the practical efficacy of our synthesized probe NAN we have employed it to recognize Al 3+ only by using a simple paper strip and estimate the concentration of Al 3+ ions in various pharmaceutical drugs and supplements as they are some of the major sources of aluminium accumulation in the human body resulting in various neurodegenerative disorders, especially Alzheimer's disease.