Novel Method for Loading Microporous Ceramics Bone Grafts by Using a Directional Flow

Abstract

The aim of this study was the development of a process for filling the pores of a β-tricalcium phosphate ceramic with interconnected porosity with an alginate hydrogel. For filling of the ceramics, solutions of alginate hydrogel precursors with suitable viscosity were chosen as determined by rheometry. For loading of the porous ceramics with the gel the samples were placed at the flow chamber and sealed with silicone seals. By using a vacuum induced directional flow, the samples were loaded with alginate solutions. The loading success was controlled by ESEM and fluorescence imaging using a fluorescent dye (FITC) for staining of the gel. After loading of the pores, the alginate is transformed into a hydrogel through crosslinking with CaCl2 solution. The biocompatibility of the obtained composite material was tested with a live dead cell staining by using MG-63 Cells. The loading procedure via vacuum assisted directional flow allowed complete filling of the pores of the ceramics within a few minutes (10 ± 3 min) while loading through simple immersion into the polymer solution or through a conventional vacuum method only gave incomplete filling.

Mechanical Properties of the Composite Material consisting of β-TCP and Alginate-Di-Aldehyde-Gelatin Hydrogel and Its Degradation Behavior

“…The elemental analyses by means of EDX and XRD proved beyond doubt that the RMS ceramic, as well as the Curasan ceramic, were phase pure β-TCP. We have already performed similar verifications for RMS ceramics in the past [ 16 , 20 , 23 ].…”

“…The loading of the porous ceramics with the hydrogels was carried out, as we previously described [ 16 , 20 ], by means of a flow chamber developed by our group. By means of this flow-through chamber, it is possible to achieve a loading of porous ceramics in a flow which is achieved by a pressure difference between the reservoir tank (normal pressure) and the flow-through chamber (low vacuum of 50 mbar).…”

About the Mechanical Strength of Calcium Phosphate Cement Scaffolds

“…Elemental analysis using EDX (Ca/P ratio 1.53) and XRD (Rietveld refinement with profex 4.3) yielded 99% β-TCP, as observed in similar studies by our group followed by Rietveld refinement analysis. We have already performed similar verifications for the sinter ceramics in the past [22,37,38]. The Rietveld refinement analysis of the 3D-printed scaffolds resulted in a main phase of HA of about 46%, followed by 27% α-TCP, 18% DCPA and 9% CDHA.…”

Monocytes enter microporous β-TCP ceramics

“…As this work to our knowledge is the rst one to use the ow chambers described in Seidenstuecker et al 2015 (31) to examine interactions of β-TCP with blood components we would also like to propose the idea of loading these ow chambers with various blood suspensions as a potential new model for in-vitro interactions of blood components and β-TCP suitable for monocytes (Fig. 2, Table 1), granulocytes (Fig.…”