Collagen is a protein with unique chemistry and a specific function. In the proper form, collagen has many responsibilities in the body, including aiding cellular activity and providing an organized matrix in skin. An understanding of collagen's chemical, physical, and biological properties will help clinicians utilize collagen technology effectively in their wound care practice and protocols.
Collagen molecule chemistry
Molecules self assemble into fibers
Aggregates become skin tissue
Transmission electron microscopy illustrates that the structure of bovine collagen fibers presented in textbooks, (left) closely resembles the structure of fibers found in dressings containing collagen in its proper form. (right)
These fibrils are 0.5 µm in diameter with repeat structural units that result in periodic striations
Collagen in Proper Form
These fibrils are 0.5 µm in diameter. Fibrils self assemble to form fibers and aggregates.
Collagen has specific chemistry, fibrillar structure, and aggregate structure. In the proper form, collagen has functional and biological properties which are lacking in improper collagen and other materials.
Collagen: 20 weeks ar 20x magnificationWhen in the proper form, collagen is replaced by newly deposited collagen (blue) in the body
Collagen composite: 20 weeks at 20x magnificationProduces a response that is similar to non collagen materials. There is a lack of newly deposited collagen (blue) and a presence of foreign body giant cells (purple).
Alginate: 20 weeks at 20x magnificationOther materials can cause foreign body responses
Collagen in the proper form has an ordered structure
Fibers self assemble into aggregates which resemble rope-like structures
Soluble collagen: Lacks nonhelical domains, forms disorganized fibrils
Insoluble Collagen: No ordered structural matrix.
Simple hydrogel: Lacks any organized structure