No abstract

Carbon dots (CDs) have drawn considerable research interest for their attractive applications in sensors, bioimaging, and photonic devices. Here, an aqueous gelatin solution is employed as the only reactant to directly generate a CDs/gelatin composite through a green and simple one‐step microwave approach. The resulting CDs/gelatin composite owns a typical excitation‐dependent photoluminescence property that comes from CDs, which can be potentially applied for multicolor fluorescence bioimaging. More importantly, the CDs/gelatin composite possesses a thermoresponsive sol–gel transition property that is associated with gelatin, which can be exquisitely enlisted to fabricate CDs/gelatin gel beads and fluorescent gel patterns. Also the release of CDs from the gel beads can be triggered by the thermoresponsive sol–gel transition. Thus, for the first time this study creates the CDs/gelatin composite with both thermoresponsive sol–gel transition and fluorescence properties, which is promising for applications in stimuli‐responsive materials, nanocomposites, controlled release, and fluorescence imaging.

Quantum dots (QDs) have drawn great attention for their attractive applications ranging from light-emitting diodes to fluorescence bioimaging. In this study, for the first time, ZnS QDs/gelatin nanocomposites with a thermo-responsive sol–gel transition property were directly prepared using a facile and green one-pot method. The method shows advantages such as the environmentally friendly strategy, mild conditions, no need for organic solvents, and simple post-treatment. In this method, gelatin not only serves as the green capping agent for the preparation of QDs but also acts as the main component in the QDs/gelatin nanocomposites. Moreover, gelatin confers its thermo-responsive sol–gel transition property to QDs/gelatin nanocomposites. The sol–gel transition property can be used to produce QDs/gelatin gel beads. Also, the release of QDs from the QDs/gelatin beads can be triggered by the thermally responsive sol–gel transition. In addition, the resulting nanocomposites can be utilized for fluorescence bioimaging. Thus, the QDs/gelatin nanocomposites with the thermo-responsive sol–gel transition property have potential uses in the controlled release, fluorescence labeling, and imaging.