Here we report a novel electrophoretic deposition technology for assembling surface-roughened inorganic nanoplatelets into ordered multilayers that mimic the brick-and-mortar nanostructure found in the nacreous layer of mollusk shells. A thin layer of sol-gel silica is coated on smooth gibbsite nanoplatelets in order to increase the surface roughness to mimic the asperity of aragonite platelets found in nacres. To avoid the severe cracking caused by the shrinkage of sol-gel silica during drying, polyelectrolyte polyethyleneimine is used to reverse the surface charge of silica-coated-gibbsite nanoplatelets and increase the adherence and strength of the electrodeposited films.
View Article and Find Full Text PDFJ Mater Sci Mater Med
August 2007
A novel method of coating a polymeric scaffold with a dense ceramic layer was developed. This method exploits the fact that only one of the two interlaced 3-D channels formed in a ceramic dual-scaffold can be infiltrated with a polymer. Firstly, a 3-D graphite network prepared by the rapid prototyping (RP) method was dip-coated with hydroxyapatite (HA) slurry, followed by heat-treatment at 1250 degrees C for 3 h in air.
View Article and Find Full Text PDFA novel scaffold designed for tissue engineering applications, which we refer to as a "dual-scaffold" because its structure consists of two interlaced three-dimensional (3-D) hydroxyapatite (HA) networks, was fabricated using a combination of the rapid prototyping (RP) method and dip-coating process. To accomplish this, a graphite network acting as a template was prepared using the RP method and then uniformly dip-coated with HA slurry. The resultant sample was then heat-treated at 1250 degrees C for 3 h in air to remove the graphite network and consolidate the HA networks.
View Article and Find Full Text PDFA combination of bi-axial machining and lamination was used to fabricate macrochanneled poly (epsilon-caprolactone) (PCL)/hydroxyapatite (HA) scaffolds. Thermoplastic PCL/HA sheets with a thickness of 1 mm, consisting of a 40 wt% PCL polymer and 60 wt% HA particles, were bi-axially machined. The thermoplastic PCL/HA exhibited an excellent surface finish with negligible tearing of the PCL polymer and pull-out of the HA particles.
View Article and Find Full Text PDFJ Biomed Mater Res A
December 2005
In this report, bioactive calcium phosphate (CaP) coatings were produced on titanium (Ti) by using phosphate-based glass (P-glass) and hydroxyapatite (HA), and their feasibility for hard tissue applications was addressed in vitro. P-glass and HA composite slurries were coated on Ti under mild heat treatment conditions to form a porous thick layer, and then the micropores were filled in with an HA sol-gel precursor to produce a dense layer. The resultant coating product was composed of HA and calcium phosphate glass ceramics, such as tricalcium phosphate (TCP) and calcium pyrophosphate (CPP).
View Article and Find Full Text PDFJ Biomed Mater Res B Appl Biomater
October 2005
Phosphate-based glass (P-glass) and poly(epsilon-caprolactone) (PCL) composites were fabricated in a sheet form by solvent extraction and thermal pressing methods, and the antibiotic drug Vancomycin was loaded within the composites for use as a hard-tissue regenerative. The degradation and drug-release rate of the composites in vitro were tailored by modifying the glass composition: 0.45 P(2)O(5)-x CaO-(0.
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