Polymeric articles modified with hyaluronate

DETAILED DESCRIPTION OF THE INVENTION The following examples (wherein all parts given are by weight unless otherwise specified) illustrate the several embodiments of the invention, without however being a limitation thereof, the invention being solely defined by the claims.
EXAMPLE 1 A Polyurethane Based Composition With Hyaluronate Bonded To The Surface And Having Improved Biocompatability Properties Sodium hyaluronate (Na-HA) is activated using the cyanogen bromide method, which has been used to attach proteins and polypeptides to cellulose or Sephadex (Cafe, M.
C.
, Pryce, N.
and Robb, I.
D.
Polymer [1976] 17, 91).
0.
1 g of NaHA was dissolved in 40 ml of distilled water.
0.
04 g of CNBr was dissolved in 2 ml of distilled water.
The cyanogen bromide solution was added to the NaHA solution and the mixture was stirred for 4 hours at room temperature, while keeping the pH constant at 11 by periodic inspection using a pH meter.
To this activated NaHA solution, polyurethane samples were added and the solution left a further 18 hours at room temperature and at pH 11.
The presence of hyaluronate on the surface of the polyurethane was established by staining with Methylene Blue dye after repeated washings with distilled water.
EXAMPLE 2 In this example, an improved polyurethane article was prepared which consists of a polyurethane matrix with sodium hyaluronate distributed throughout the body and on the surface of that matrix.
A 7% solution of Polyetherurethane (80AE) (PEUU) was prepared by shaking the polymer in dimethylformamide (DMF).
A sodium hyaluronate (NaHA) solution in dimethylsulphoxide and water was prepared by taking 2-8 mg of Na-HA, preswelling with approximately 0.
75 ml of distilled water or just sufficient to wet it and leave no supernatant, allowing to stand for 10-15 minutes and then adding 20-25 ml of dimethysulphoxide (DMSO) to give a clear viscous solution of sodium hyaluronate.
The PEUU solution in DMF was added to the DMSO solution of Na-HA in the ratio of 1 to 0.
7, and if any precipitation occurred the solution was warmed to 40