| MadSci Network: Chemistry |
Spider silk is biodegradable for a good reason - the spiders need to reuse it. They break it down with enzymes (proteases) and reabsorb the raw materials.
Silk is protein; like hair, or nails. Like keratin (hair, nails) or collagen (skin fiber), silk has a very simple, repetitive structure. This is what moth silk looks like:
So it is simply a series of strands arranged alternately up and down, in layers. However, this is only the structure at the lowest, molecular level. In spider silk, similar molecular strands are arranged into tiny crystalline regions of the fiber while the rest of the fiber is more loose. It is this mixture of crystalline and plastic regions that is thought to give silk its properties of both strength and stretchiness.
So. How to prevent it decomposing. Short answer : no idea. However, I'll give you my best guess!
The most obvious possibility is simply to make artificial silk out of a material that does not decompose so readily. Well, I say "simply", but obviously this has caused much difficulty so far for research groups trying to make artificial silks.
Two approaches come to mind : coating the fiber, and using non-protein amino acids. Both might, of course, affect the properties of the silk - in other words, make it worse at doing its job! However, it is possible that using synthetic materials could improve the silk - spiders have silk that has been evolved for their needs, not ours.
In fact, I notice you are actually asking about storage, not synthesis. I suppose that like all biological fibers (wool, cotton, etc) silk should be stored away from heat, light, and damp. I tried to find a reference for the oldest surviving silk garment; I'm sure that they exist.
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