ABSTRACT: Lanthanide-based upconversion nanoparticles
(UCNPs) are a new type of luminescent tags that show great
application potential in biomedical fields. However, a major
challenge when applying UCNPs in biomedical research is the
lack of a versatile strategy to make water-dispersible and
biocompatible UCNPs with high simplicity in functionalization.
To address this problem, in the present work, we employed 6-
phosphate-6-deoxy-β-cyclodextrin (βPCD) as the novel ligand to
fabricate a versatile upconversion luminescent nanoplatform. Using
βPCD as the surface ligand not only enhances the stability and
biocompatibility of the UCNPs under physiological conditions but
also enables simple conjugation with various functional molecules,
such as organic dyes and biomolecules, via the host−guest
interaction between those molecules and the cyclodextrin cavity.
The conjugated upconversion nanoprobe then displays excellent capability in labeling the cancer cells and tumor tissue slices for
luminescent imaging. These results demonstrate that the versatile cyclodextrin-functionalized upconversion nanoplatform
appears particularly flexible for further modifications, indicating great potential for applications in biosensing and bioimaging