Siderophore coated magnetic iron nanoparticles: Rational designing of water soluble nanobiosensor for visualizing Al 3+ in live organism.

This article aims to establish the judicious use of iron-binding chemistry of microbial chelators in order to functionalize the surface of iron nanoparticles to develop non-toxic nanobiosensor. Anchoring a simple siderophore 2,3-dihydroxybenzoylglycine (H3 L), which bears catechol and carboxyl functionalities in tandem, on to the surface of Fe3 O4 nanoparticles has developed a unique nanobiosensor HL-FeNPs which showed highly selective and sensitive detection of Al3+ in 100% water at physiological pH. The biosensor HL-FeNPs, with 20nM limit of detection, behaves reversibly and instantly. In-vivo bio-imaging in live brine shrimp Artemia confirmed that HL-FeNPs could be used as fluorescent biomarker for Al3+ in live whole organisms. Magnetic nature of the nanosensor enabled HL-FeNPs to remove excess Al3+ by using external magnet. To our knowledge, the possibility of microbial chelator in the practical development of Al3+ selective nanobiosensor is unprecedented.