Additive Manufacturing Technologies for Enhancing the Development Process of Biodevices - Advanced Design and Manufacturing Technologies for Biomedical Devices - page 196

Fig. 10.21 Different Matlab-based CAD designs of microtextured scaffolds and prototypes manu-
factured in epoxy resin using laser stereolithography and fi nal diamond-like carbon coating for
improving biocompatibility. See Chap. 15 for ex vivo trial of h-MSC upon these scaffolds
(Additional details: (Díaz Lantada et al. 2012 ) )

transparent. In such case, light penetrates easily through the material and several
layers can be polymerized at a time, thus eliminating the pores and inner details
included in the CAD design. In order to limit light penetration and improve preci-
sion, organic colorants can be used, such as curcuma.
Figure 10.12 shows the effect of different proportions of colorant and exposure
times on fi nal woodpile structure. It can be seen that the manufacture of patterned
thin sheets for cell growth studies is possible, even though structuring larger and
more complex parts needs further research. Anyway superposition of thin sheets
can also lead to fi nal 3D structures, and if the sheets are previously patterned with
cells and nutrients and added to each other, when cells are already growing, some
interesting results connected with the fi eld of biofabrication might be obtained.
Another possibility, if the biodevices or scaffolds are not aimed at fi nal long-term
implantation, is the use of a protective coating upon more conventional rapid proto-
typing materials, such as epoxy or acrylic resins. Such bio-coating, normally obtained
by physical or chemical vapor deposition (see Chap.

13 ) , can help with ex vivo trials
for assessing the effect of microtextures, pore sizes, and overall scaffold morphology
on cell growth and subsequent differentiation into relevant tissues.
However, if implanted, progressive deterioration or delamination of the coating
(due to combined mechanical and chemical effects) could possibly lead to the basis
material being in contact with corporal tissues and producing undesirable effects.
Figure 10.21 shows different Matlab-based CAD designs of microtextured scaf-
folds and the rapid prototypes manufactured in epoxy resin using laser stereolithog-
raphy, which here benefi t from a fi nal diamond-like carbon (DLC) coating for
improving biocompatibility. Compact coatings were obtained, with thickness of
around 100 nm, by deposition at room temperature using the vacuum fi lter cathodic