ABSTRACT
The natural or synthetic materials existing in the environment interact differently with living organisms depending on their form. Compared to bulk material, powders and fibers do not generally show the same toxicity or biocompatibility. In nature, bulk material generally interacts with the skin while powdered material also interacts with the lungs, the eyes, and the digestive tract, due to its ability to remain in suspension in air or water. Components of the complement can also bridge the particle to the cells. They can be adsorbed at the material surface due to its chemical properties. Sodium urate crystals absorb fibronectin, complement, and a number of other proteins on their surfaces. More generally, at the molecular level, it is believed that the state and species of adsorbed proteins significantly influence the extent of material-mediated inflammatory responses. Inflammation is a reaction of the microcirculation characterized by movement of fluid and circulating cells from the blood into the extravascular sector.
