This paper deals with carrier materials for drug delivery based on chemically bonded ceramics (CBC), and specifically Ca-aluminates (CA). The property profile of these CBC-biomaterials and their microstructures give these materials potential as carriers for drugs. The paper describes in some detail the CA carrier system with regard to the technology and chemistry, the biocompatibility and specifically the microstructure and the related loading possibilities of the drugs in the carrier material. The development of microstructures includes different types of porosity, amount of porosity, pore size and pore channel size, and combination of different porosity structures. Specific surface area measurements (BET) of dried fully hydrated Ca-aluminate yield BET- values of > 400 m~2 /g, corresponding to a hydrate size of approximately 25 nm, and pore channel sizes of 1-10 nm, in accordance with values from the high-resolution TEM analysis. Complementary porosity above 10 nm is obtained by partial hydration of the precursor material or excess of water in the hydration step, and pore sizes > 100 nm by inert ceramic fillers with phases of oxides of Ti, Si, Ba or Zr, the latter phases selected in order also to increase strength and radio-opacity of the carrier systems discussed. The carrier material can be applied as a solid or a suspension for different types of intake. The drug carrier can also work as an injectable implant.
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