Aqueous near-infrared fluorescent composites based on apoferritin- encapsulated PbS quantum dots

A study was conducted to demonstrate the synthesis of an aqueous soluble near-infrared (NIR) fluorescent composite, based on a PbS quantum dot (QD), entrapped in the hollow core of a horse spleen apoferritin (AFt) protein case. The synthesis was performed by two different approaches,such as reassembly and nanoreactor processes. It was demonstrated that the reassembly method involves disassembly of the AFt shell into its component protein subunits and reassembly of the protein shell in the presence of performed PbS QDs. The study also demonstrated that the AFt-PbS construct provides a stable fluorescent composite in the NIR. It was demonstrated that this property of the composite combines with its solubility in water and that AFt provides an exterior protein coat to the QD that allows covalent attachment of other biomolecules, using chemical techniques.