Highly luminescent quantum dots functionalized and their conjugation with IgG

A sol–gel approach including partially removing capping agents, depositing SiO2 monomers, and growing a SiO2 shell was developed to generate a bio-compatible functionalization on CdTe quantum dots (QDs). The QDs retained their high photoluminescence (PL) efficiency after coating with a SiO2 shell (22.5%) by controlling the surface state of the QDs to decrease PL degradation during a sol–gel preparation. Furthermore, the CdTe QDs with a SiO2 shell were conjugated with IgG using 3-sulfo-N-hydroxysuccinimide or streptavidin–maleimide as linkers. The biotin–streptavidin linker resulted in a high PL efficiency retained (only ∼23% lower than the initial value of the QDs), which is crucial for bio-applications.

Graphical abstractA sol–gel approach was developed to prepare highly luminescent SiO2-coated CdTe quantum dots where they further conjugated with IgG using 3-sulfo-N-hydroxysuccinimide or streptavidin–maleimide as linkers.Figure optionsDownload full-size imageDownload high-quality image (57 K)Download as PowerPoint slide