FRET Ratiometric Nanoprobes for Nanoparticle Monitoring.

Fluorescence labelling is often used for tracking nanoparticles, providing a convenient assay for monitoring nanoparticle drug delivery. However, it is difficult to be quantitative, as many factors affect the fluorescence intensity. Förster resonance energy transfer (FRET), taking advantage of the energy transfer from a donor fluorophore to an acceptor fluorophore, provides a distance ruler to probe NP drug delivery. This article provides a review of different FRET approaches for the ratiometric monitoring of the self-assembly and formation of nanoparticles, their in vivo fate, integrity and drug release. We anticipate that the fundamental understanding gained from these ratiometric studies will offer new insights into the design of new nanoparticles with improved and better-controlled properties.

Antifouling Surfaces Enabled by Surface Grafting of Highly Hydrophilic Sulfoxide Polymer Brushes.

Antifouling surfaces are important in a broad range of applications. An effective approach to antifouling surfaces is to covalently attach antifouling polymer brushes. This work reports the synthesis of a new class of antifouling polymer brushes based on highly hydrophilic sulfoxide polymers by surface-initiated photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization. The sulfoxide polymer brushes are able to effectively reduce nonspecific adsorption of proteins and cells, demonstrating remarkable antifouling properties. Given the outstanding antifouling behavior of the sulfoxide polymers and versatility of surface-initiated PET-RAFT technology, this work presents a useful and general approach to engineering various material surfaces with antifouling properties, for potential biomedical applications in areas such as tissue engineering, medical implants, and regenerative medicine.