Fibronectin 1, also known as fibronectin, the English name is fibronectin (English abbreviation FN), is a high molecular glycoprotein discovered by foreign research in 1974 and has a variety of biological functions. FN is widely present in animal tissues and tissue fluids. It is a macromolecular glycoprotein with a molecular weight of approximately 450KD and has a variety of biological activities. A large number of domestic and foreign research results have proven that FN molecules are highly conserved during evolution. FN in various animal body fluids have very similar structures, properties and biological functions, so FN from different sources can be used interchangeably. my country's applied research on FN started late. At present, domestic fibronectin (FN) is mainly imported from abroad. However, during many years of research on fibronectin (FN), many achievements in fibronectin (FN) have been made. National invention patent.