Emulsification and other physicochemical changes in polydimethylsiloxanes (PDMS)
exposed to model systems representing eye-ball tissue, human blood serum and collagen
Polimery 2001, No 6, 428
SummaryEmulsification of a silicon oil within the human eye was studied by using oversimplified eye-ball models. A silicon oil composed of 1 g high-viscosity silicon oil (Silol 5000) and 4 mL of a solution including a vitreous body fluid, blood serum or collagen were prepared to simulate the environment inside the human eye-ball and to observe its behavior after the oil has been injected. The resulting two-phase systems were incubated and shaked for 8 weeks at 37oC. The effect of additives including a low-viscosity (300 cSt) siloxane and a polysiloxane containing silanol (Si-OH) groups on emulsification was also studied. Silol 5000 was found to produce stable emulsions. the strongest being the one formed in combination with the vitreous body fluid. The emulsion formation rate was not affected by the additives examined. The physiological fluids, which are surface active, exhibit spontanuous emulsifyng properties toward silicones. One possible reason for the production of stable emulsions is the formation of protein-silicon complexes at phase boundaries. An indirect supporting evidence was found in the IR spectra recorded upon prolonged exposure in vivo of tissues and eye-ball fluids to a silicon oil Oxane 5700.