Silk yog ib qho protein fiber, tseem hu ua silk fibroin. Nws yog ib tug nitrogen-muaj polymer compound, lub hauv paus ntawm nws macromolecule yog alpha amino acid. Cov qauv qauv dav dav ntawm α amino acids yog RCH (NH2) COV. Vim tias nws pawg amino nyob rau ntawm α carbon atom ntawm ib sab ntawm pawg carboxyl lossis carboxylic acid, nws hu ua α amino acid. Raws li cov qauv txheej txheem ntawm silk fibroin molecules, sab pawg txuas nrog cov pab pawg peptide sib txawv nyob rau hauv tag nrho cov macromolecular saw txawv, uas yog ib qho tseem ceeb feature ntawm natural protein fibers.
Muaj 18 hom amino acids uas tsim los ntawm silk fibroin. Cov ntsiab lus ntawm txhob lo lo ntxhuav fibroin suav txog li 70% -80% ntawm txhob lo lo ntxhuav. Ntawm lawv, glycine (gly), alanine (ala) thiab serine (ser) suav txog li 80% ntawm tag nrho cov muaj pes tsawg leeg.
