Interactions of stealth conjugated polymer nanoparticles with human whole blood.

Photoluminescent conjugated polymeric nanoparticles (CPNs) exhibit favourable properties as fluorescent probes due to their brightness, high photostability, tunable emission spectra and ease of surface modification. Potential cellular and clinical applications of these new diagnostic agents are easily envisioned, providing a rationale to study CPN biocompatibility. Here, stealth formulations of poly phenylene vinylene (PPV) and poly phenylene ethinylene (PPE) were manufactured and their interactions with human blood components assessed.

Gd-containing conjugated polymer nanoparticles: bimodal nanoparticles for fluorescence and MRI imaging.

Aqueous bifunctional semiconductor polymer nanoparticles (SPNs), approximately 30 nm in diameter (as measured from electron microscopy), were synthesised using hydrophobic conjugated polymers, amphiphilic phospholipids and a gadolinium-containing lipid. Their fluorescence quantum yields and extinction coefficients were determined, and their MRI T₁-weighted relaxation times in water were measured. The bimodal nanoparticles were readily taken up by HeLa and murine macrophage-like J774 cells as demonstrated by confocal laser scanning microscopy, and were found to be MRI-active, generating a linear relationship between T₁-weighted relaxation rates and gadolinium concentrations The synthesis is relatively simple, and can easily result in milligrams of materials, although we fully expect scale-up to the gram level to be easily realised.