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Ideally, implants should inhibit nonspecific protein adsorption, bacterial adhesion, and at the same time, depending on the final application be selective toward cellular adhesion and spreading for all or only selected cell types. Poly(L‐lysine)‐grafted‐poly(ethylene glycol) (PLL‐g‐PEG) polymers have been shown to adsorb from aqueous solution onto negatively charged metal oxide surfaces, reducing protein adsorption as well as fibroblast, osteoblast and epithelial cell adhesion significantly. PLL‐g‐PEG can be functionalized with bioligands such as RGD (Arg‐Gly‐Asp), which then restores host cell adhesion, but the surface remains resistant to nonspecific protein adsorption. Previously, it was also shown that both nonfunctionalized PLL‐g‐PEG and RGD‐peptide functionalized PLL‐g‐PEG reduced the adhesion of Staphylococcus aureus to titanium (Ti) surfaces. The present study looked at the effect of other implant associated infection relevant bacteria, Staphylococcus epidermidis, Streptococcus mutans and Pseudomonas aeruginosa towards the same surface chemistries. The different surfaces were exposed to the bacteria for 1–24 h, and bacteria surface density was evaluated using scanning electron microscopy (SEM) and fluorescence light microscopy (FM). The adhesion of all bacteria strains tested was reduced on Ti surfaces coated with PLL‐g‐PEG compared to uncoated Ti surfaces even in the presence of RGD. The percentage reduction in bacterial adhesion over the 24‐h culture time investigated was 88%–98%, depending on the bacteria type. Therefore, coating surfaces with PLL‐g‐PEG/PEG‐RGD allows cells such as fibroblasts and osteoblasts to attach but not bacteria, resulting in a selective biointeractive pattern that may be useful on medical implants. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008 [ABSTRACT FROM AUTHOR]

Fracture fixation devices are implanted into a growing number of patients each year. This may be attributed to an increase in the popularity of operative fracture care and the development of ever more sophisticated implants, which may be used in even the most difficult clinical cases. Furthermore, as the general population ages, fragility fractures become more frequent. With the increase in number of surgical interventions, the absolute number of complications of these surgical treatments will inevitably rise. Implant-related infection and compromised fracture healing remain the most challenging and prevalent complications in operative fracture care. Any strategy that can help to reduce these complications will not only lead to a faster and more complete resumption of activities, but will also help to reduce the socio-economic impact. In this review we describe the influence of implant design and material choice on complication rates in trauma patients. Furthermore, we discuss the importance of local delivery systems, such as implant coatings and bone cement, and how these systems may have an impact on the prevalence, prevention and treatment outcome of these complications. [ABSTRACT FROM AUTHOR]

Highlights: [•] Novel models of pre- and postoperative bacterial adhesion were developed. [•] Preoperative model: bacterial adhesion was increased on rough compared to smooth PEEK. [•] A novel oxygen plasma treatment did not alter bacterial adhesion in the preoperative model. [•] Postoperative model: oxygen plasma treatment had a species specific effect. [•] Both pre and postoperative adhesion should be considered when evaluating biomaterials. [Copyright &y& Elsevier]

Implanted biomaterials are coated immediately with host plasma constituents, including extracellular matrix (ECM); this reaction may be undesirable in some cases. Poly(l-lysine)-grafted-poly(ethylene glycol) (PLL-g-PEG) has been shown to spontaneously adsorb from aqueous solution onto metal oxide surfaces, effectively reducing the degree of non-specific adsorption of blood and ECM proteins, and decreasing the adhesion of fibroblastic and osteoblastic cells to the coated surfaces. Cell adhesion through specific peptide-integrin receptors could be restored on surfaces coated with PLL-g-PEG functionalized with peptides of the RGD (Arg–Asp–Gly) type. To date, no study has examined the effect of surface modifications by PLL-g-PEG-based polymers on bacterial adhesion. The ability of Staphylococcus aureus to adhere to the ECM and plasma proteins deposited on biomaterials is a significant factor in the pathogenesis of medical-device-related infections. This study describes methods for visualizing and quantifying the adhesion of S. aureus to smooth and rough (chemically etched) titanium surfaces without and with monomolecular coatings of PLL-g-PEG, PLL-g-PEG/PEG-RGD and PLL-g-PEG/PEG-RDG. The different surfaces were exposed to S. aureus cultures for 1–24 h and bacteria surface density was evaluated using scanning electron microscopy and fluorescence microscopy. Coating titanium surfaces with any of the three types of copolymers significantly decreased the adhesion of S. aureus to the surfaces by 89–93% for PLL-g-PEG, and 69% for PLL-g-PEG/PEG-RGD. Therefore, surfaces coated with PLL-g-PEG/PEG-RGD have the ability to attach cells such as fibroblasts and osteoblasts while showing reduced S. aureus adhesion, resulting in a selective biointeraction pattern that may be useful for applications in the area of osteosynthesis, orthopaedic and dental implantology. [Copyright &y& Elsevier]