Fig. 9
From: Nanobio applications of quantum dots in cancer: imaging, sensing, and targeting
Schematic illustration resuming the different bioconjugation methods. a Use of a bifunctional ligand such as mercaptoacetic acid for covalent linkage of NCs to biomolecules. b TOPO-capped NCsbound to a modified acrylic acid polymer by hydrophobic interaction. Then, biomolecules are covalently attached. c NC solubilization and bioconjugation by exchanging TOPO against mercaptosilane, additional silanization and finally covalent linkage to a biomolecule. d Creation of negatively charged NCs through ligand exchange, then adsorption of biomolecule via electrostatic interactions. e Incorporation of NCs intonanobeads, then linkage to biomolecules (Geissbuhler 2005)