Temperature responsive nanoparticles: poloxamers as a modulator of Forster resonance energy transfer (FRET)

摘要

An effective strategy to control the Forster resonance energy transfer (FRET) of a donor/acceptor emitter pair that were attached to a 60 nm poly(propargyl acrylate)(PA) nanoparticle using temperature variations was developed. The size dependent properties of a poly-(ethylene oxide)-poly-(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) block copolymer (poloxamer) was exploited to vary the spatial separation of the emitters and vary the FRET efficiency. Specifically, a 2 change in FRET efficiency between the donor/acceptor pair was achieved per 1 degrees C change in temperature from 49 degrees C to 60 degrees C when using a poloxamer of 2950 g mol(-1) molecular weight, with sections of PPO consisting of 32 repeat units, PEO sections consisting of 12 repeat units and a lower critical solution temperature (LCST) of 58 degrees C. The methodology presented in this effort is easily extended to other temperature regimes through a judicious choice in poloxamer and corresponding LCST.