Simultaneous Immobilization of Bioactives During 3D Powder Printing of Bioceramic Drug‐Release Matrices

Advanced Functional Materials (Impact Factor: 11.81). 05/2010; 20(10):1585 - 1591. DOI: 10.1002/adfm.200901759


The combination of a degradable bioceramic scaffold and a drug-delivery system in a single low temperature fabrication step is attractive for the reconstruction of bone defects. The production of calcium phosphate scaffolds by a multijet 3D printing system enables localized deposition of biologically active drugs and proteins with a spatial resolution of approximately 300 µm. In addition, homogeneous or localized polymer incorporation during printing with HPMC or chitosan hydrochloride allows the drug release kinetics to be retarded from first to zero order over a period of 3–4 days with release rates in the range 0.68%–0.96% h−1. The reduction in biological activity of vancomycin, heparin, and rhBMP-2 following spraying through the ink jet nozzles is between 1% and 18%. For vancomycin, a further loss of biological activity following incorporation into a cement and subsequent in vitro release is 11%. While previously acknowledged as theoretically feasible, is its shown for the first time that bone grafts with simultaneous geometry, localized organic bioactive loading, and localized diffusion control are a physical reality. This breakthrough offers a new future for patients by providing the required material function to match patient bone health status, site of repair, and age.

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Available from: Elke Vorndran
    • "The main benefits of low temperature 3D printing is its capability to construct polymer/mineral composites with increased material properties to include growth factors and drugs to enhance bone regeneration or combat infection.[89] Fused deposition modeling has frequently utilized biomedical polymers with low melting temperatures.[90] "

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    • "To our knowledge this is the first study that reports the fabrication by rapid prototyping and under mild conditions, of drugloaded composite scaffolds with high ceramic/organic ratios. Other authors have reported systems that rely on the setting reaction of cements, an exothermic reaction that implies acidic media, both conditions that may degrade the drug [15] [16]. "
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    • "The latter is a recent method, namely low temperature 3DP, wherein a reactive liquid solution is injected into a CaP powder base [23]. The main advantage of this method is that no further thermal treatment is required, which provides the possibility for local deposition of polymers and biologically active drugs during the printing process [26]. Another promising advantage of this technique is the possibility of developing cell-based bone grafts, which have recently been reported to enhance bone regeneration, by means of combining mesenchymal stromal cells with osteoconductive scaffolds [27]. "
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