abstract
Two new examples of uncommon three-dimensional Ca-bearing metal organic frameworks, [Ca(H2O)(3)(HPXBP)] (CaP1) and [Ca-2(H2O)(2)(HPXBP)(1.5)] (CaP2) (PXBP: p-xylylenebisphosphonate), were prepared and their structures characterized by single crystal X-ray diffraction. CaP1 crystallizes in the monoclinic C2/c space group, with three water molecules occupying a half coordination sphere on one side of the Ca atom, while CaP2 crystallizes in the triclinic P (1) over bar space group, with two crystallographic unique Ca atoms, each coordinated by a single water molecule. In contrast with CaP2, which exhibits very low bioactivity, CaP1 readily precipitates bone-precursor phases (octacalcium phosphate, OCP, and hydroxyapatite) in SBF solutions. Moreover, studies with MG63 osteoblast-like cells indicate that CaP1 is not toxic and stimulates bone mineralization and, thus, holds considerable potential for treating bone diseases, such as osteoporosis.
keywords
OCTACALCIUM PHOSPHATE; PROTON CONDUCTIVITY; APATITE-FORMATION; VITAMIN-D; BISPHOSPHONATES; BIOACTIVITY; MECHANISM; HEALTH; MILK
subject category
Chemistry
authors
Shi, FN; Almeida, JC; Helguero, LA; Fernandes, MHV; Knowles, JC; Rocha, J
our authors
João Rocha
Full Professor
José Carlos Martins de Almeida
Junior Researcher
Maria Helena Figueira Vaz Fernandes
Retired ProfessorGroups
1 - inorganic functional nanomaterials and organic-inorganic hybrids
3 - carbon materials, composites and functional coatings
5 - biomedical and biomimetic materials
acknowledgements
This work was developed in the scope of the project CICECO-Aveiro Institute of Materials (ref. FCT UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when applicable cofinanced by FEDER under the PT2020 Partnership Agreement. We acknowledge projects CENTRO-07-ST24-FEDER-002030, MI-PI-36-ARH/2012, MI-PI-08-ARH/2014, PTDC/CTM-NAN/119994/2010 and grant PTDC/SAU-ONC/118346/2010 (LAH). Dr. Rosario Soares help in the grazing incidence XRD measurements is acknowledged.