Sea sponge spicules - Application prospects of biological skeletons from the Cambrian period

Sea sponge spicules refer to the skeleton of the simplest multicellular organism, sponges, which grow in marine environments. The main skeleton and support are glassy siliceous spicules, and there are also calcareous spicules.

Source of sea sponge spicules

Sponges, phylum Poros, are a diverse and globally distributed branch of benthic organisms, whose evolutionary history can be traced back to at least the Ediacaran-Cambrian boundary (541 million years ago). Throughout the history of sponge research, it has been a hot research object in many fields such as paleontology, evolutionary biology, and even bioengineering and pharmacology. The main feature of sea sponge spicules is the presence of mineral elements called spicules, which structurally support the sponge body while minimizing the metabolic cost of water exchange and deterring predators. The description of spicule shape and skeletal organization is the basic foundation of sponge classification and systematics.

Research prospects of sea sponge spicules

The main skeleton and support of sponges in two of the three main sponge classes are glass fiber-like silica spicules. Recently, people have discovered the unique microstructure and good optical fiber properties of silica sponge spicules, especially pointing out that these properties bring new ideas for manufacturing optical fibers to humans, and soon aroused scientists' extensive research interests in biology, mineralogy and bionics on its structure, properties, growth mechanism and regulation.

Bionic significance of sea sponge spicules

Metal oxides (titanium oxide and gallium oxide, etc.) with optoelectronic and semiconductor properties are synthesized under non-natural conditions (high temperature, high vacuum and corrosive environment). Obviously, this production model does not conform to today's environmental concepts. However, the magical marine organisms, under completely natural environmental conditions, use Si and O that are ubiquitous in nature to build materials with better performance than artificial optical fibers, which points out a new bionic technology path for humans to synthesize high-performance electronic and optical materials under environmentally friendly conditions. The research team of the University of California, Santa Barbara has successfully catalytically synthesized amorphous TiO2 under neutral and low temperature conditions using silica protein extracted from sponge spicules as a template. Recently, they synthesized a molecular layer with a dual role of catalysis and molecular template on the surface, similar to the sponge spicule protein filaments, and biomimetic synthesis of metal gallium hydroxide (GaOOH) and oxide (γ-Ga2O3) semiconductor materials.

In short

Sea sponge spicules have achieved a natural and near-perfect technical blueprint after millions of years of natural evolution, providing a new energy-saving and "environmentally friendly" technology for humans to use nanobiotechnology to biomimetic synthesis of bio-inorganic mineral materials, and have broad biomimetic application prospects in the fields of optical fiber, microelectronics and biomedical materials.