AVS 51st International Symposium
    Biomaterial Interfaces Monday Sessions
       Session BI-MoP

Paper BI-MoP36
Effects of He, Ar Ion Implantation on the Surface Chemistry and Structure of Biomedical Polymers

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: M. Manso Silvan, Institute for Health and Consumer Protection, European Commission, Italy
Authors: M. Manso Silvan, Institute for Health and Consumer Protection, European Commission, Italy
A. Valsesia, Joint Research Centre, European Commission, Italy
M. Lejeune, Joint Research Centre, European Commission, Italy
D. Gilliland, Joint Research Centre, European Commission, Italy
G. Ceccone, Joint Research Centre, European Commission, Italy
F. Rossi, Joint Research Centre, European Commission, Italy
Correspondent: Click to Email
Ion beams have become during the last years an outstanding tool for the processing of biomedical devices due to their ability to modify the structural and chemical properties of polymers. The surface chemistry, determinant factor in the performances of biosensor and tissue engineering devices, can be tailored by exposure to ion beams in different ranges of energies and ion doses. Regarding the case of noble gas implantation (Ar, He) at energies from 25 up to 100 KeV, we have found that the surfaces of biomedical polymers such as Polymethylmethacrylate (PMMA), Polystyrene (PS), Polycaprolactone (PCL) and Polyethyleneglycol (PEG) can be notably modified by exposure to doses below 10@super 14@ cm@super -2@. These transformations were applied to adapt the polymer stability in aqueous media or the surface activity towards protein attachment. A series of physico-chemical characterization tools were used in order to follow the surface and structural changes related to the implantation conditions. Fourier transformed infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectroscopy (ToF-SIMS) were used to monitor compositional changes of the implanted samples before and after interaction in biomolecular assays at protein and peptide level. Atomic force microscopy (AFM) and Ellipsometry revealed topographic and structural changes while contact angle and Zeta potential measurements evidenced changes in the molecular interaction of the polymers surface. In particular, it is shown that relevant modifications can be observed in polymer samples exposed to identical ion doses but with beams characterized by different ion density.