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 H-1 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.

Automated summary

A new fluorescent chemosensor (NAN) comprising 2-hydroxy naphthaldehyde and 1,8-naphthalic anhydride demonstrated high selectivity for aluminium ions compared to other bio-relevant metal ions. The addition of Al3+ to the probe solution under a UV-lamp induced a rapid transformation from non-fluorescent to bright blue fluorescence, with a remarkably low detection limit of 33 nM. The interaction mechanism between the metal ion and NAN was thoroughly investigated using techniques such as absorbance, fluorescence, and H-1 NMR titration, and confirmed by detailed theoretical calculations. To showcase its practical efficacy, our synthesized probe NAN was utilized for the recognition of Al3+ using a simple paper strip, enabling the estimation of Al3+ ion concentrations in various pharmaceutical drugs and supplements, which are major sources of aluminium accumulation in the human body and associated with neurodegenerative disorders, particularly Alzheimer's disease.