Tissue lubricant, natural

The colorless character of these oils is important in some cases, because it may indicate the chemically inert nature of the hydrocarbon constituents. Textile lubricants should be colorless to prevent staining of light-colored threads and fabrics. Insecticide oils should be free of reactive (easily oxidized) constituents so as not to injure plant tissues when applied as sprays (ASTM D-483). 

Macroscopically Non-stimulative Surfaces. When a biomaterial moves relative to the contacting tissue, the tissue surface is often damaged by mechanical abrasion resulting, for instance, in stenosis for the case of tubular tissues such as the urethra (1). Most of the inner and outer surfaces of soft tissues are lubricious because the surface is covered with a mucous layer though skin is one exception. Due to this lubricity serious damage to the tissue surfaces can be avoided even if they are brought in frictional contact with each other. In contrast to natural tissues, artificial materials generally do not possess such lubricious surfaces. A method to render the artificial surface lubricious is to coat it with a hydrophilic layer. 

Hyaluronic acid is a linear polysaccharide that is naturally present in the ECM of mammalian connective tissues. It is composed of alternating disaccharide units of oc-l,4-D-glucuronic acid and p-l,3-7V-acetyl-D-glucosa-mine, and it shows a very peculiar rheological behavior including remarkable viscoelasticity and shear-dependence, which have been related to a lubricating... 

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