Enhancing silicon quantum dot uptake by pancreatic cancer cells via pluronic encapsulation and antibody targeting

Objectives: Silicon quantum dots (SiQDs) are of great interest for bio-imaging applications due to their tunable luminescence, low toxicity, unique surface chemistry, and high quantum yield. Most synthesis routes produce SiQDs that are not water-dispersible, making them unattractive for biological applications. Here, we show that Pluronic block copolymers can encapsulate SiQDs to make them water dispersible and suitable for cancer imaging applications. Methods: Transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential, and temperature and pH stability measurements were used to evaluate these Pluronic -encapsulated SiQDs (PSiQDs). The particles were also tested targeted in vitro imaging and in vivo bio-distribution. Results: Encapsulation with Pluronic polymers renders the SiQDs water dispersible, preserves their optical properties, protects them from oxidation, and prevents aggregation. Surface modification of the PSiQDs with pancreatic cancer targeting moieties, anti-claudin-4 and anti-mesothelin, led to enhanced uptake of these nanoconstructs in comparison to PSiQDs modified with folate as the targeting moeity. Conclusions: The particles are stable at biological conditions, and show promise for targeted diagnostic applications without possessing elementally toxic components.