Highly stable conjugated polymer dots as multifunctional agents for photoacoustic imaging-guided photothermal therapy.

Theranostic nanomedicines involved in photothermal therapy (PTT) have received constant attention as promising alternatives to traditional therapies in clinic. However, most photothermal agents are limited by their instability and low photothermal conversion efficiency. In this study, we report a new conjugated polymer dots (Pdots) as multifunctional agents for photoacoustic (PA) imaging-guided PTT. The novel BDT-IID Pdots are readily fabricated though nanoreprecipitation and can absorb strongly in 650-700 nm region. Furthermore, BDT-IID Pdots possess the stable nanostructure and extremely low biotoxicity. In particular, its photothermal conversion efficiency can be up to 45%. More importantly, our in vivo results exhibit that the BDT-IID Pdots are able to offer concurrently enhanced PA contrast and sufficient photothermal effect. Consequently, the BDT-IID Pdots can be exploited as a unique theranostic nanoplatform for PA imaging-guided PTT of tumors, holding great promise for their clinical translational development.