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In vitro evaluation of degradable electrospun polylactic acid/bioactive calcium phosphate ormoglass scaffolds

Majchrowicz Anna, Roguska A., Krawczyńska A., Lewandowska M., Martí‑Muñoz J., Engel E., Castano O.

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 2

296--306

EN

Nowadays, the main limitation for clinical application of scaffolds is considered to be an insufficient vascularization of the implanted platforms and healing tissues. In our studies, we proposed a novel PLA-based hybrid platform with aligned and random fibrous internal structure and incorporated calcium phosphate (CaP) ormoglass nanoparticles (0, 10, 20 and 30 wt%) as an off-the-shelf method for obtaining scaffolds with pro-angiogenic properties. Complex morphological and physicochemical evaluation of PLA–CaP ormoglass composites was performed before and after in vitro degradation test in SBF solution to assess their biological potential. The degradation process of PLA–CaP ormoglass composites was accompanied by numerous CaP-based precipitations with extended topography and cauliflower-like shape which may enhance bonding of the material with the bone tissue and accelerate the regenerative process. Random fiber orientation was preferable for CaP compounds deposition upon in vitro degradation. CaP compounds precipitated firstly for randomly oriented composite nonwovens with 20 and 30 wt% addition of ormoglass. Moreover, the preliminary bioactivity test has shown that BSA adsorbed to PLA–CaP ormoglass composites (both aligned and randomly oriented) with 20 and 30 wt% of ormoglass nanoparticles which was not observed for pure PLA scaffolds.

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Ca-deficient hydroxyapatite scaffolds from injectable calcium phosphate/chitosan cements

Rajzer I., Castano O., Engel E., Planell J. A.

Engineering of Biomaterials

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2010

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Vol. 13, no. 92

2--4

EN

Calcium phosphate cement (CPC) has been success-fully used in bone tissue regeneration for many years. However, poor mechanical properties and low biodegradation rate limit any further applications. R-cement has a higher solubility than conventional CPC and its reaction products (CDHA) are similar to the mineral phase of bone. In this work we have developed new CPC composition which consists of a mix of cement R, glycerol as a liquid phase carrier and a biodegradable hydrogel (chitosan) which acts as a binder and was incorporated into R-cement to strengthen this biomaterial. The cement past was found to be stable in a syringe (even after two month of storage in the freezer) and hardened only after being exposed to biological fluids.

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An ultrasonic method for estimation of elastic properties of R-bone cement after immersion in Ringer's solution

Rajzer I., Piekarczyk J., Castano O., Engel E., Planell J. A.

Engineering of Biomaterials

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2008

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Vol. 11, no. 81-84

113--116

EN

The aim of this investigation is to establish an improved non-destructive ultrasonic through-transmission technique to monitor the setting behaviour of calcium phosphate cement samples. On the basis of ultrasound techniques the elastic properties of cement paste after different soaking time in Ringer's solution were measured. Young's modulus, the rigidity modulus, and Poisson's ratio were calculated from measurements of density and ultrasonic longitudinal and shear wave velocities.