Vaterite Research Articles

Effect Of Local Modulation In Enzymatic Homeostasis On Bone Turnover Marker Dynamics In Blood At Substituting Femur Defects With Vaterite Scaffolds

The goal of this research was the investigation of concentration changes in the blood bone turnover markers during local modulation of enzymatic homeostasis by means of targeted delivery of alkaline phosphatase (ALP) with polycaprolactone (PCL) and vaterite (VT) scaffolds implanted into the femur defects in white rats. Material and Methods ― The tests of PCL/VT/ALP scaffold implantations into the bone defects were performed on 30 white rats, and the serum of intact animals was used as the control. ELISA and multiplex assay were used to find inflammatory and bone turnover markers including monocyte chemoattractant-1, sclerostin, fibroblast growth factor-23, connective tissue growth factor (CTGF), osteoprotegerin, osteocalcin, β-сross laps and the activity of tartrate-resistant acid phosphatase-5b in the blood of experimental animals. The activity of serum ALP was tested with the conventional kinetic method. The morphology of the reparative processes was verified by microscopy of specimens taken from the implantation areas and stained with hematoxylin or eosin. Results ― The PCL/VT/ALP scaffold implantations into the bone defects of white rats caused active osteogenesis along with the steady rise in osteocalcin concentration in blood. ALP activity in the blood did not depend on the exogenous enzyme in the scaffold and rose by the 28th day after the implantations. The targeted ALP delivery into the defect area caused the rise in CTGF concentration as well as the decrease in blood sclerostin within a short time after the implantations. Conclusion ― The modulation of the local enzyme homeostasis by means of the targeted ALP delivery with PCL/VT scaffolds stimulated reparative osteogenesis within a short time after the implantations with no changes to the bloodstream or local inflammatory changes suggesting their biocompatibility and the safety in use.

Bio-sequestration of CO2 Using Carbonic Anhydrase in situ Encapsulated Inside Electrospun Hollow Fibers

Carbonic anhydrase catalyzed bio-sequestration of CO2 to form HCO3-, followed by trapping as solid CaCO3 is one of the most promising technologies for CO2 capturing. The effects of reaction condition on the CO2 hydration using free carbonic anhydrase were systematically investigated. In order to improve the stability of the enzyme and facility its recycling, the carbonic anhydrase was in situ encapsulated inside hollow fibers via a novel co-axial electrospinning technology. Compared with the free enzyme, the immobilized carbonic anhydrase showed much improved thermal stability and suffered much reduced inhibitory effects from cation ions, such as Cu2+ and Fe3+. After 11 reuses, the immobilized enzyme retained about 81.9% of its original activity by comparing the amount of formed CaCO3 precipitation. In the presence of immobilized carbonic anhydrase, both calcite and vaterite CaCO3 solid were formed; while in the absence of enzyme or with free carbonic anhydrase, only calcite CaCO3 was observed.

Sub‐Micrometer Vaterite Containers: Synthesis, Substance Loading, and Release

Sub‐Micrometer Vaterite Containers: Synthesis, Substance Loading, and Release

Vaterite in freshwater cultured pearls from China and Japan

Vaterite in freshwater cultured pearls from China and Japan

On the Reported Presence of Vaterite and Aragonite in Coccoliths of Emiliania huxleyi

On the Reported Presence of Vaterite and Aragonite in Coccoliths of Emiliania huxleyi

The occurrence of vaterite in gastropod egg-shells

The occurrence of vaterite in gastropod egg-shells