Fabrication of a luminescent chemosensor for selective detection of Al3+ 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 Al3+ 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 1H 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 Al3+ only by using a simple paper strip and estimate the concentration of Al3+ 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.