Biomedical Engineering Reference
In-Depth Information
Chinese hamster lung (CHL) fibroblasts [103]. Typical results from cell com-
patibility tests of P3HB films using L929 mouse fibroblasts are shown in
Figs. 5 and 6 [72]. Melt-spun P3HB fibers [104, 105] also support L929 mouse
fibroblast adhesion, as shown in Fig. 6c.
Canine anterior cruciate ligament fibroblasts cultured in highly porous
P3HB-9%3HV scaffolds sustained a cell growth similar to that observed
in collagen sponges [106]. On the other hand, human scoliotic fibroblasts
isolated from spinal ligaments exhibited low proliferation rates on P3HB-
3HV (7%, 14%, 22% 3HV) surfaces, independent of the copolymer compo-
sition [107]. P3HB-8%3HV was found to be slightly more compatible than
P3HB-12%3HV in terms of L929 fibroblast proliferation, cytotoxic effect, and
cytokine production [108].
A limited cell compatibility of plasticized P3HB-3HV was observed in
a study using NIH 3T3 mouse fibroblasts, and was attributed to leaching of
plasticizers [109]. Thus, the potential toxicity of leachables such as plasti-
cizers or other additives has to be considered when conducting cell culture
experiments. Additionally, removal of remaining solvent is crucial if polymer
films are prepared by solution-casting, which is the most widely used method
for sample fabrication in cell culture studies. It has been shown that storage
of solution-cast polymer films even under vacuum does not allow for com-
plete chloroform removal (Fig. 7), so that solvent may be released from the
polymer film during cell culture experiments.
The relatively low surface wettability of P3HB solution-cast film surfaces
(contact angle 68
◦
[94, 110]) has been discussed as a limiting factor for cell
attachment and growth. Strategies to improve cell compatibility of P3HB
include methods to increase the surface wettability (decreasing water con-
Fig. 5
Cell viability of L929 mouse fibroblasts after 3 and 5 days of culture on solution-
cast P3HB films, compared to that of P3HB films modified with 30% at-P3HB, dg-P3HB,
TEC (leached), and BTHC; PLLA films for comparison [72]
