Random lasing from kombucha bacterial cellulose-ZnO bionanocomposite foam

Random lasers (RLs) with biological and natural origins have attracted a great deal of attention in biosensing and bio-imaging. In this work, we described a high-performance RL based on kombucha bacterial cellulose and ZnO bionanocomposite foam. The foam was constructed by coating a high-scattering ZnO material on the 3D scaffold cellulose fibers of a KBC. This provides a high level of scattering, which enables light to be better confined within the structures, thus facilitating resonance feedback for random lasing emission. By implementing organic dye molecules into the bionanocomposite foam, we successfully achieved a random lasing emission with a low threshold of 110 & mu;J mm-2. Due to the RL's high flexibility and high elasticity, it is able to shift the lasing emission wavelengths to the longer range induced by the folding effect. Compared to other RLs based on natural materials, our RL showed a lower lasing threshold. The biocompatibility and biodegradability of the nanocomposite materials together with the simple, two-step, and low-cost RL fabrication process highlight the promising future of using the proposed RLs in many optical, biological, and medical applications.