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Abstract Calcium phosphate is the most important inorganic constituent of biological tissues, and synthetic calcium phosphate has been widely used as biomaterials. In this study, a facile method has been developed for the fabrication of amorphous calcium phosphate (ACP)/polylactide-block-monomethoxy(polyethyleneglycol) hybrid nanoparticles and ACP porous nanospheres. Europium-doping is performed to enable photoluminescence (PL) function of ACP porous nanospheres. A high specific surface area of the europium-doped ACP (Eu3+:ACP) porous nanospheres is achieved (126.7 m2/g). PL properties of Eu3+:ACP porous nanospheres are investigated, and the most intense peak at 612 nm is observed at 5 mol% Eu3+ doping. In vitro cytotoxicity experiments indicate that the as-prepared Eu3+:ACP porous nanospheres are biocompatible. In vitro drug release experiments indicate that the ibuprofen-loaded Eu3+:ACP porous nanospheres show a slow and sustained drug release in simulated body fluid. We have found that the cumulative amount of released drug has a linear relationship with the natural logarithm of release time (ln(t)). The Eu3+:ACP porous nanospheres are bioactive, and can transform to hydroxyapatite during drug release. The PL properties of drug-loaded nanocarriers before and after drug release are also investigated.

Electrospinning is one of the most simple and effective methods to prepare polymer fibers with the diameters ranging from nanometer to several micrometers. Poly(L‐lactide)‐co‐poly (ɛ‐caprolactone) (P(LLA‐CL)) fibers and P(LLA‐CL)/heparin coaxial composite fibers herein were successfully prepared by single electrospinning and coaxial electrospinning, respectively. The prepared endothelialized P(LLA‐CL) and P(LLA‐CL)/heparin vascular grafts were used in the Beagle dogs experiment to evaluate the feasibility of thus made different scaffolds for substitution of dog femoral artery in early period, medium term, and long term, meanwhile the pure P(LLA‐CL) vascular graft was used as the control group during all the experiments. The animal model was established by using the graft materials to anastomose both femoral arteries of dogs. The vascular grafts patency rates (i.e., the unobstructed capacity of blood vessel) were detected by color Doppler flow imaging technology and digital subtraction angiography. To observe the histological morphology at different periods, the vascular grafts were removed after 7, 14, and 30 days, and the corresponding histological changes were evaluated by hematoxylin and eosin staining. The experimental results show that in the early period, the patency rates of pure P(LLA‐CL) graft, endothelial P(LLA‐CL) graft, and P(LLA‐CL)/heparin graft were 75%, 75%, and 100%, respectively; in the medium term, the patency rates of pure P(LLA‐CL) graft and endothelial P(LLA‐CL) graft were 25%, whereas that of P(LLA‐CL)/heparin graft was 50%; the patency rates of pure P(LLA‐CL) graft and endothelial P(LLA‐CL) graft were down to 0%, whereas the patency rate of P(LLA‐CL)/heparin graft was 25% in the long term. This preliminary study has demonstrated that P(LLA‐CL)/heparin coaxial composite fiber maybe a reliable artificial graft for the replacement of femoral artery. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 471–478, 2019. [ABSTRACT FROM AUTHOR]