While seemingly a myriad of polymer-based nanoparticles for targeted delivery of drugs have been created, it is still difficult to gauge how many actually reach their final destination and deliver the cargo. Researchers at the Agency for Science, Technology and Research (A*STAR) in Singapore have created a way of incorporating quantum dots into polymer nanoparticles to allow for easy tracking of the nanoparticles within the body.
Quantum dots are tiny crystals that can be created to reflect light at specific wavelengths. The researchers developed a way of using poly(D,L-lactide-co-glycolide), or PLGA, as the encapsulating material to be able to either carry any of a number of different drugs or the specially tuned quantum dots. Using a mix of both, the researchers can inject the polymer nanoparticles and then use a laser to illuminate the target and measure how many are reaching the target from the returning fluorescence.
From the study abstract in journal Small:
The use of quantum dots enables efficient detection and precise quantitation of cellular uptake of particles which occupy 25% of the cell volume. The correlation of quantum dot- and doxorubicin-incorporated nanoparticles is useful to develop an evaluation platform for nanoparticle formulations through imaging and quantitation. This platform is also used to observe the surface properties effect of other polymers such as chitosan and poly(ethylene) glycol on the cellular interaction and uptake. Moreover, quantum dots can be used to study microparticle theranostic delivery formulations by deliberately incorporating as visible ring surrounding the microparticles for their easy identifying and tracing in diagnostic and chemotherapeutic applications.