AVS 47th International Symposium
    Biomaterial Interfaces Wednesday Sessions
       Session BI-WeP

Paper BI-WeP17
Microbial Adhesion on Polymer: Role of Morphological and Chemical Properties in the Micro-organism Behaviour

Wednesday, October 4, 2000, 11:00 am, Room Exhibit Hall C & D

Session: Poster Session
Presenter: M. Anderle, ITC-irst, Italy
Authors: M. Anderle, ITC-irst, Italy
R. Canteri, ITC-irst, Italy
E. Carli, ITC-irst, Italy
S. Janikowska, ITC-irst, Italy
A. Lui, ITC-irst, Italy
C. Pederzolli, ITC-irst, Italy
G. Speranza, ITC-irst, Italy
D. Maniglio, Università di Trento, Italy
C. Della Volpe, Università di Trento, Italy
Correspondent: Click to Email
Infections caused by implanted polymeric devices (especially catheters) have an increasing importance in the medical routine (up to 40% of nosocomial infections). The critical event in the pathogenesis of foreign body infection is the adhesion of the micro-organisms to the biomaterial surfaces followed to the colonisation. In order to achieve a deeper understanding of the molecular-level interactions between catheters and biological system, the aim of this work is to study the physicochemical properties of the polymeric surface and their influence on the microbial adhesion and colonisation. Some common polymers produced by standard processing methods have been analysed by dynamic contact angle (DCA), X-ray Photoelectron Spectroscopy (XPS), Time of Flight Sims (TOF Sims) and Scanning electron microscope (SEM). Moreover biological tests were performed to determine the degree of gram+ and gram- bacterial adhesion on these surfaces. The results show relevant deviation of the contact angles from the expected values. These results are only partially explained by the XPS and the TOF Sims analysis. XPS and TOF Sims spectra revealed normally contaminated polymer surfaces and deviations from the nominal composition also after accurate cleaning, performed using different methods. In particular oxidation of the polymer surface occurring probably during the moulding process and other factors are able to introduce chemical functions which lead to a surface chemistry significantly different from the expected one. High value of contact angle and unexpected values of bacteria adhesion can be explained taking into account the presence of basic functions and the roughness of the surface. These elements decrease the differences expected on the basis of the acid, basic or dispersive characters of the examined polymers.