What are practical uses for spider silk?

Spider silk protein has many glycine and alanine resides, which are hydrophobic and cause the protein to fold into a fibrous shape. More than 1,000 individual polypeptide chains hydrogen bond and hydrophobically interact with one another to form long silk fibers. Because of the strength arising from its protein structure, spider silk is much desired for human uses. Using genetic engineering, biologists have been able to harvest composite silk fibers produced by silkworms in industrial quantities. Now that this composite silkworm–spider silk is available, numerous applications (functions related to structure) can be contemplated. For example, a recent study compared surgical sutures made from spider silk with widely used sutures made from synthetic fibers to hold together injured tendons. The spider silk sutures were far superior, holding their strength over many cycles of tendon movement during healing. Another application on the horizon is bulletproof vests: the energy required to break a spider silk filament is at least 100 times greater than the energy of a typical bullet in impact.

Future directions

Perhaps the most widespread use for spider silk may be in textiles. By definition, textiles are flexible materials made of natural or artificial fibers (threads) that are woven together. The clothes you are wearing are textiles, perhaps made of cotton fibers (made up of cellulose) or polyester fibers (an artificial polymer) or a combination. Of course, silk fibers from silkworms have a long history in textiles, particularly in Asia. The addition of spider silk fibers, or combined spider–silkworm silk to existing textiles, holds great promise to increase the strength and in some cases the flexibility of the textile.