Using cadmium telluride quantum dots as a proton flux sensor and applying to detect H9 avian influenza virus

Semiconductor nanocrystals, often known as quantum dots, have been used extensively for a wide range of applications in bioimaging and biosensing. In this article, we report that the pH-sensitive cadmium telluride (CdTe) quantum dots (QDs) were used as a proton sensor to detect proton flux that was driven by ATP synthesis in chromatophores. To confirm that these QD-labeled chromatophores were responding to proton flux pumping driven by ATP synthesis, N,N′-dicyclohexylcarbodiimide (DCCD) was used as an inhibitor of ATPase activity. Furthermore, we applied the QD-labeled chromatophores as a virus detector to detect the H9 avian influenza virus based on antibody–antigen reaction. The results showed that this QD virus detector could be a new virus-detecting device.