Quantum dot induced cellular perturbations involving varying toxicity pathways

The unique optical and electronic properties of quantum dots (QD) have led to rapid progress in their development and application, particularly in innovative therapeutic and diagnostic products. Along with the great pace at which QD are being developed, research is being focussed on fabricating less toxic QD with novel surface functionalities. The present study was therefore focused on assessing the impact of varying QD surface chemistry on cellular uptake and a range of indicators for cell perturbation following exposure. The study demonstrated that despite a low intrinsic cytotoxicity of three QD with different surface functional groups, they were all capable of inducing an acute inflammatory response and alterations in transcriptional gene activity, without affecting cell cycle regulation. Further, this investigation demonstrated that although the QD were capable of inducing an inflammatory and oxidative stress response, there was clearly variation in the degree of molecular change according to surface chemistry, which correlated with the degree of cellular uptake. These findings therefore highlight the potential for chronic inflammatory responses following exposure to QD, but in addition, they also demonstrate the importance of studying a wide range of toxicity pathways to generate a comprehensive picture of biological response to nanomaterials.