Nanostructure Engineering May Benefit Medical Coatings Applications

Researchers at the State Key Laboratory of Electroanalytical Chemistry at the Chinese Academy of Sciences (CAS; Beijing) have demonstrated the potential of using biofilms for nanostructure engineering. Describing the use of biofilms as engineering materials for nanostructures and demonstrating it using zinc oxide nanorods, the scientists says that since biofilms are gel-like matrices that can be adhered on several substrates, such bilateral adhesive behavior can be employed to immobilize the nanostructures on various types of substrates. Because of the material's excellent biocompatibility, this strategy can perhaps be marshaled to produce medical coatings and other biomedical products.

While biofilms are generally viewed as pathogenic threats, their complex frameworks, biological behavior, chemical heterogeneity, and physical structure at the micro- and the nanoscale can also be useful in nanofabrication.

Led by Xiurong Yang, a professor at the Changchun Institute of Applied Chemistry, the researchers present strategies that can be applied to the immobilization, fabrication, and organization of nanostructures as long as they can be prepared in an aqueous solution and the precursors can react with a bacterium. Their research shows that biofilms can be an efficient and low-cost approach for large-scale fabrication of various nanostructures.

Using the example of zinc oxide nanostructures, the CAS team explored the use of biofilms in three aspects: immobilization, morphological organization, and selective permeability. They began with the fermentation of Streptococcus thermophilus, a lactic acid bacterium. They then used the resulting biofilm to immobilize zinc oxide nanorods on a polystyrene substrate with a curved surface (the inner wall of a centrifuge tube). These as-grown zinc oxide nanostructures remained quite stable after irradiation sterilization. This technique also worked on other substrates, such as glass, silicon, and indium tin oxide.

"The ingenious structure of biofilms can lead to the synthesis of fantastic nanostructure devices, even beyond the fabrication capability of the current state-of-the-art methods," the authors say.