Collagen shields types

Kalluri R, Torre A, Shield CF III, et al. Identification of alpha3, alpha4, and alphas chains of type IV collagen as alloantigens for Alport posttransplant anti-glomerular basement membrane antibodies.Transplantation. 2000 69 679-683. 

There are two distinct types of hardeners. One contains free formaldehyde, commonly responsible for irritant and allergic reactions these hardeners are only sold periodically, when popular (Norton 1991). In the United States, the FDA regulations require that they contain no more than 5% formaldehyde, have a protective shield for the nail, be applied only to the free end of the nail, and be labelled with warnings of side effects (Food and Drug Administration 1994). The second type of hardener encompasses nail enamels marketed as hardeners. They may have a high resin content, decreased amount of plasticizer, and additions, such as collagen, calcium, or minute fibers. 

Type I collagen is used in a number of medical devices including hemostats, eye shields and cosmetic implants and has extensive potential in the growth of ti.ssues in cell culture. Therefore, it is essential to understand the purification, characterization and usage of t pe I collagen. ... 

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