title: Liquid- and solid-state high-resolution NMR methods for the investigation of aging processes of silicone breast implants.
abstract: To investigate aging processes of silicone gel breast implants, which may include migration of free unreacted material from the gel and rubber to local (e.g. connective tissue capsule) or distant sites in the body, chemical alteration of the polymer and infiltration of body compounds, various approaches of multinuclear nuclear magnetic resonance (NMR) experiments (29Si, 13C, 1H) were evaluated. While 29Si, 13C, and 1H solid-state magic angle spinning (MAS) NMR techniques performed on virgin and explanted envelopes of silicone prostheses provided only limited information, high-resolution liquid-state NMR techniques of CDCl(3) extracts were highly sensitive analytical tools for the detection of aging related changes in the materials. Using 2D 1H, 1H correlation spectroscopy (COSY) and 29Si, 1H heteronuclear multiple bond coherence (HMBC) experiments with gradient selection, it was possible to detect lipids (mainly phospholipids) as well as silicone oligomer species in explanted envelopes and gels. Silicone oligomers were also found in connective tissue capsules, indicating that cyclic polysiloxanes can migrate from intact implants to adjacent and distant sites. Furthermore, lipids can permeate the implant and modify its chemical composition.
authors.affiliation: Department of Clinical Radiology, University of Münster, Albert-Schweitzer-Strasse 33, D-48149 Münster, Germany.
authors.forename: Anja Britta
authors.initials: AB
authors.lastname: Birkefeld
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Bertermann
authors.forename: Hellmut
authors.initials: H
authors.lastname: Eckert
authors.forename: Bettina
authors.initials: B
authors.lastname: Pfleiderer
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D018427:Breast Implants / Q000009:adverse effects*; D003238:Connective Tissue / Q000737:chemistry; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008055:Lipids / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D020034:Silicone Gels / Q000737:chemistry*; D013997:Time Factors
chemical_list: D001672:Biocompatible Materials; D008055:Lipids; D020034:Silicone Gels