Biomedical Engineering Reference
In-Depth Information
An important aspect toward the development of future bioactive materials coated with
LbL films is the stability of the anchoring of the films to the materials. If physisorption
does not lead to sufficiently strong interactions, other strategies such as covalent attach-
ment of the first layer or grafting of mussel adhesive-inspired polymers can be envisioned
(see Section 8.2.2). Future tests will have to evaluate these aspects of film resistance toward
mechanical stresses in the framework of specific applications (vascular tissue engineering,
bone tissue engineering, etc.).
In Vivo Studies on PEM-Coated Materials
In vitro studies must be followed by in vivo studies to investigate the effects of the coatings
in a more complex biological environment and for a specific purpose. As the studies on
PEM films and animal and human cells started only about 8 years ago, the in vivo studies
on PEM films began to emerge only 4 years ago. The number of in vivo studies has grown
rapidly over the past years (four articles published in 2009). Table 8.2 shows all the in vivo
studies to date.
The first studies have been published in 2005 for films deposited on tracheal prostheses
(Schultz et al. 2005) or deposited on model surfaces and implanted in the rat mouth (Etienne
et al. 2005b) or in the mouse peritoneal cavity (Picart et al. 2005b). Films containing poly-
saccharides such as chitosan and hyaluronan were found to be biodegradable, which can
probably be attributed to the presence of enzyme in body fluids (hyaluronidase, lyzozyme,
etc.). Recently, a porous titanium implant coated with a film containing a specific peptide
(laminin-5 derived peptide) proved to induce the formation of specific adhesive structures
called hemidesmosomes. In addition, the implant was colonized by the cells of the soft
surrounding tissue. Nichols et al. (2009) explored the possibility to create an artificial bone
marrow construct by using inverted colloidal crystals coated with a PDDA/platelet film. A
high vascularization was observed around the construct and the presence of both mature
and immature precursor cells was also evidenced.
Acknowledgments
The authors are grateful to the following funding agencies for their support over the past
years through research and equipment grants as well as a postdoctoral (KR) and a PhD fel-
lowship (TC): “Association Française contre les Myopathies” (AFM), “Association pour la
Recherche sur la Cancer” (ARC), CNRS, “Fondation Recherche Médicale” (FRM), “Agence
Nationale pour la Recherche” (ANR PNANO program), and by the NIH (R21 grant).
ListofAbbreviations
ALG: alginate
BDNF: brain-derived neurotrophic factor
BMP:
bone morphogenetic protein
BSA:
bovine serum albumin (BSA)
 
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