Conjugated Structure of Quantum Dots and Magnetic Nanoparticles Connected to Folic Acid for Biological Applications
Written by Merav Muallem
Merav Muallem, Lioz Etgar, Efrat Lifshitz
Semiconductor quantum dots (QD) and magnetic metal oxides nanoparticles (NPs) possess unique properties. QDs-NPs conjugated structures can be utilized in new and emerging technologies such as magnetic transport, separation and fluorescence tagging of cancer cells, bacteria or viruses. In order to use the conjugated semiconductors QDs - NPs in biological applications it has to be soluble in aqueous solution. Hence, the organic capping (ligands) processing hydrophobic moiety were replaced by water soluble ligands with hydrophilic functional groups, giving the opportunity to conjugate structures with drugs and targeted cells. In order to use this conjugated structure as fluorescence probe for cancer cell diagnosis, a recognition group, such as folic acid (FA) molecule was attached to the QDs’ external surface. Folic acid has very high binding affinity to folate receptor (FR), which is over-expressed on human tumor cells. Consequently the conjugate structure (QDs-NPs) connected to folic acid (FA) molecule should create a system that could diagnose cancer cells on their first stages.