(633d) The Improved Adhesion Behavior of Fibroblasts On Anodized 316L Stainless Steel

Introduction: It is now recognized that surface nanostructures on biomaterials greatly influence cellular behaviors as well as surface biochemical
properties[1, 2]. Nano-featured surfaces might be used as an
excellent bioactive interface for implantable materials. Stainless steel is one of
the most important alloys for biomedical applications. However, their bioinert characteristic
surface is a disadvantage for numerous applications. The aim of this study was
to fabricate nano-structured surfaces on 316L stainless steel by an anodization
method and
examine the effects of these anodized nano-surfaces on the attachment of fibroblasts.

Materials & Methods: 316L stainless
steel (2.0 mm °Á 2.0 cm °Á 0.5 mm) (Goodfellow Cambridge Ltd. England) was anodized
at 30 V
for 4 min in ethylene
glycol containing 10 vol. % perchloric acid to create bioactive surfaces. The surface morphology
and elemental composition of 316 L
after anodization were characterized by scanning electron microscopy (SEM,
Hitachi S-4800, Tokyo, Japan) and energy-dispersive X-ray
analysis (EDAX). Fibroblasts were seeded on the samples to evaluate initial cellular
responses to the nano-structured surfaces. After cell culturing for 4 hours,
the attachment of fibroblasts was determined by a methyl thiazolyl
tetrazolium (MTT) assay. Smoothly polished 316L was used as control surfaces. Light microscopy
and SEM were used to observe the morphology of cells. Experiments
were completed in triplicate and repeated at least three times. Data were
analyzed statistically using student t-test.

Results and Discussion: A
nano-porous structure was successfully fabricated by the anodization procedure. The
pore sizes were about 100 nm. After 4 hours of culture, the fibroblasts adhered well on the
surfaces of all the stainless steel specimens. SEM images showed that
fibroblast exhibited normal morphology and were able to penetrate into pores by
long filopodia. MTT tests indicated that
the anodization
of 316 L stainless steel
significantly promoted a higher degree of cell adhesion as
compared to the polished 316L
stainless steel after 4 hours. (p<0.05)
(Fig. 1).

Conclusions: The findings in this study
showed that anodization significantly improved the initial cell-material
interactions on the 316L
stainless steel. Although further work is required to determine the long-term
effects of the anodized surfaces on the proliferation and
differentiation of cells, the results of this study indicated that the
anodized
surfaces of the 316L
stainless steel had better biological activity.

References

1. Mart¨ªnez
E, Engel E, Planell, JA, Samitier, J. Ann Anat 2009; 191: 126-135.

2. Ercan
B, Taylor E, Alpaslan E, Webster TJ. Nanotechnology 2011; 22:
295102