Tuning and Targeting Semiconducting Polymer Nanoparticles to Enhance In Vivo Photoacoustic Imaging

Photoacoustic (PA) imaging is a novel imaging technique that combines the high spatial resolution of ultrasound imaging and the specificity of optical imaging techniques. To achieve good contrast in vivo, PA imaging relies on the optical properties of endogenous molecules. However, many clinically relevant biological species are optically silent, and would require an imaging agent to target them with good specificity while remaining photostable and retaining good bioavailability. Recently, the Tabor group has succeeded in specifically targeting a pDNA delivery nanoparticle to EGFR receptors, overexpressed on the surface of cancer cells, by introducing pendant targeting peptides into the nanoparticle scaffold. Coformulated with lipids and amphiphilic moieties such as PEG and DPPC, these coated nanoparticles have good retention times and their functionalised core remains protected from degradation. Based on the recent synthesis by the Bronstein group of indigo-derived semiconducting polymers (INDT-X) with excellent PA potential, the aim of this project is to formulate EGFR-targeting INDT species within a semiconducting polymer nanoparticle (SPN) scaffold, to produce a safe and performant PA contrast agent for the clinical and pre-clinical imaging of a variety of cancers.