Poly(lactide-co-glycolide) (PLGA) nanofibrous composite scaffolds having nano-hydroxyapatite particles (HAp) in the fibers were prepared by electrospinning of PLGA and HAp with an average diameter of 266.6 ± 7.3 nm. Microscopy and spectroscopy characterizations confirmed integration of the crystalline HAp in the scaffolds. Agglomerates gradually appeared and increased on the fiber surface along...

CaO-Al₂O₃-SiO₂ (CAS) as a liquid phase was introduced into hydroxyapatite (HAp) to prepare bone scaffolds. The effects of the CAS content (1, 2, 3, 4 and 5 wt%) on microstructure and mechanical properties of HAp ceramics were investigated. The optimal compression strength, fracture toughness and Vickers hardness reached 22.22 MPa, 1.68 MPa·m1/2 and 4.47 GPa when 3 wt% CAS was added, which were ...

The use of cheaper and recyclable biomaterials (like eggshells) to synthesize high purity hydroxyapatite (HAp) with better properties (small particle size, large surface area and pore volume) for applications (in environmental remediation, bone augmentation and replacement, and drug delivery systems) is vital since high-purity synthetic calcium sources are expensive. In this work, pure and meso...

Results of in situ atomic force microscopy (AFM), ex situ AFM, optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, and x-ray diffraction were combined with previous macroscopic investigations to characterize aqueous Pb(NO3)2 reaction with hydroxylapatite (Ca5(PO4)3OH) (HAP). Experiments were conducted by immersing particulate HAP crystals in the AFM fluid cell in s...

The mechanism of the formation of a self-aligned hydroxyapatite (HAP) nanocrystallite structure was examined. It is found that the highly ordered HAP nanocrystallite assembly is attributed to the so-called self-(homo)epitaxial nucleation and growth. On the other hand, according to this mechanism, a high supersaturation will give rise to a random assembly of HAP crystallites. The effects of ions...

Using the spark plasma sintering (SPS) method, hydroxyapatite (HAp) material was densified using a hydroxyapatite powder (RND Korea, 45 μm, purity 98 +%). The HAp was nearly completely dense with a relative density of up to 97 % after the simultaneous application of 60 MPa of pressure and about 30 minutes of electric current without significant change in the grain size. The average grain size o...

background : hexavalent chromium ( cr (vi)) is an important contaminant in surface and groundwater and its removal from contaminated water and wastewater has received interest in recent years. this study aimed to explain the removal process of cr (vi) from aqueous solution using nano hydroxyapatite (n-hap) as an adsorbent material. methods: cr (vi) removal experiments with the prepared n-hap we...

Bone biomineralization is a well-regulated protein-mediated process where hydroxylapatite (HAP) crystals are nucleated with preferred orientation within self-assembled protein matrix. Mimicking this process is a promising approach to the production of bone-like protein/mineral nanocomposites for bone repair and regeneration. Towards the goal of fabricating such nanocomposites from sericin, a pr...

The mobilization and biodégradation of 13 PAHs sorbed in a creosote-contaminated soil were assessed in the presence of sodium dodecyl sulphate (SDS). In a mobilization experiment, the soil was mixed with SDS solutions (0.005 to 1 % w/v) and the PAH concentrations in the aqueous phase were determined. In a biodégradation experiment, soil residual PAH concentrations were monitored during 45 weeks...

BACKGROUND Hospital-acquired pneumonia (HAP) is the most common health care-associated infection contributing to death. Studies have indicated that there may be differences in the causative pathogens and outcomes of ventilator-associated pneumonia (VAP) and non-ventilator-associated pneumonia (NV-HAP). However, with limited NV-HAP-specific data available, treatment is generally based on data fr...