[1] Univ Erlangen Nurnberg, Inst Biomat, D-91058 Erlangen, Germany
[2] Istanbul Tech Univ, Chem & Met Engn Fac, Dept Chem Engn, TR-34469 Istanbul, Turkey
[3] Univ Buenos Aires, Fac Pharm & Biochem, Dept Pharmaceut Technol, RA-1113 Buenos Aires, DF, Argentina
[4] Natl Sci Res Council, Buenos Aires, DF, Argentina
[5] Univ London Imperial Coll Sci Technol & Med, Dept Mat, London SW7 2BP, England
[6] Univ Erlangen Nurnberg, Inst Polymer Mat, D-91058 Erlangen, Germany
[7] Abo Akad Univ, Proc Chem Ctr, FI-20500 Turku, Finland