Herstellung von homogenen Hydrogel-Copolymeren

A method is provided for the preparation of homogeneous copolymers having a predetermined equilibrium water content (EWC) value formed by the addition polymerization of a mixture of ethylenically unsaturated monomer A and ethylenically unsaturated monomer B, for example, 2-hydroxyethyl methacrylate and hydroxypropyl methacrylate. The method requires determining the EWC values of the hydrogel homopolymer of hydrophilic monomer A (homopolymer A) and the hydrogel homopolymer of hydrophilic monomer B (homopolymer B); determining the relationship of the EWC values of the homogeneous copolymers AB versus the chemical composition of said copolymers AB; selecting the targeted EWC value and determining the chemical composition of copolymer AB having the targeted EWC value; forming a polymerizable mixture of monomer A and monomer B in amounts sufficient to yield copolymer AB having the targeted EWC value; and effect the polymerization reaction to yield copolymer AB characterized by the targeted EWC value. A method is also provided for the preparation of a delivery device including a drug contained in the reservoir of the hydrogel of copolymer AB, said device being characterized by its capability of eluting or releasing the drug through the hydrogel membrane to a delivery environment at a predetermined rate. There is also disclosed a sterilized kit containing a trocar or hypodermic needle/syringe and the aforesaid drug delivery device having a cylindrical shape with a rounded or bullet-like extremity.