Bioinspired synthesis of a hollow metallic microspiral based on a spirulina bioscaffold

Bioinspired synthesis approaches aim to take advantage of the morphology and structural features of biological materials for the development of functional micro/nanodevices. In this Letter, we report that a unicellular algae known as a Spirulina was applied as a bioscaffold for the synthesis of hollow metallic Cu microspirals with length of 200-300 μm. The electroless deposition method was employed to cover the spirulina forming the spiral. The nanomechanical properties of the spiral were investigated by using the nanoindentation technique. The results showed the hardness and elastic modulus of the spiral were 0.63-0.68 GPa and 12.35-12.63 GPa, respectively. Other metallic or alloy spirals could also be synthesized by using the spirulina as a bioscaffold with low cost and high reproducibility, and the obtained spirals could be promising materials as functional micro/nanodevices for microelectromechanical systems.