Biomimetic file 176: Biogenic Silica

Why ensuring scalability is crucial to long term planning

Highlight: “Chemists hoping to copy the way ocean-going organisms build intricate silica nanostructures have developed effective new mimics of two key biomolecules…Marine organisms such as sponges and diatoms make their silica skeletons by concentrating the low amounts of silicon found in seawater….By polymerising silicic acid, [Si(OH)4], into chains of alternating silicon and oxygen atoms, diatoms make complex silica exoskeltons, while sponges make spike-like ‘spicule’ structures that can reach three meters in length, while just 10 millimetres across…Scientists are attempting to understand these biological processes, with the additional aim of copying nature’s ability to make complex silica structures under mild conditions from seawater…Industrial silica – a ￡1.4 billion industry – is used in a wide variety of products….”

Insight:?There are no shortages of silica on the planet, as a matter of fact silica is one of the most abundant substances in the Earth’s crust. That is a great advantage because, as opposed to other commonly used materials such as iron or copper, we do not have to worry about silica running out and driving supply/demand instabilities.

The problem with glass (made of silica) in industrial processes is not to find it but rather that it takes a lot of energy to extract, process (melt) and treat. Looking into natural processes of silica based substrates can offer solutions to this problem; for instance deep sea organisms such as sponges can produce silica at low temperatures (3-4 degrees C) rather than the 1700 or so temperatures required in our processes!

A business point to retain here is that it is perhaps wiser to focus and develop large scale-long term strategies based on raw items that we know we have a lot of. The same applies to energy and hydrogen in particular considering the abundance of sea water. Acceptance is another issue; would you live in a silica based structural society (glass homes/cities)?

What is Biomimetics:?the field of gaining inspiration from nature first to solve some of our most difficult challenges. Instead of coming up with our own solutions to a problematic, the odds are that species or natural systems on the planet already offer?an ultimate solution. This simple fact is also another strong case to preserve species at all cost as the intellectual heritage contained within or through the study of species is both irreplaceable and invaluable…