Control of morphology and structure of calcium carbonate crystals by heparin

Abstract

Growth control of calcium carbonate crystal by organic chemicals contributes an important part to its mineralizing mechanism and biomimetic preparation. The influence of heparin (HEP) on morphology and structure of calcium carbonate generated by CaCl 2 /Na 2 CO 3 solution was studied by a scanning electron microscope, an X-ray diffraction machine, a Fourier transform infrared spectrophotometer and a fluorescent spectrophotometer. The results showed that the calcite formed in the absence of HEP, while the addition of HEP induced changes in the morphology and structure of calcium carbonate crystals. In the presence of 2.5 mg/mL HEP, calcium carbonate was stimulated to grow orientationally, forming a spherical vaterite with a diameter of 1.5 m. By X-ray diffraction, the contents of vaterite were counted to be 57.43% and 64.9% in the presence of 5 mg/mL and 20 mg/mL HEP, respectively. The resulted CaCO 3 /HEP microspheres achieved an 80% efficiency for HEP encapsulation. These results may provide novel references for studying the mechanism of biomineralization and the synthesis of HEP-functionalized materials. heparin, calcium carbonate crystal, heparin-functionalized materials Citation:Liu X R, Zhu B Q, Shao Y Y, et al. Control of morphology and structure of calcium carbonate crystals by heparin.

Fabrication of heparinized hierarchically hollow hydroxyapatite microspheres as bone substitute for controlled growth factors delivery

“…In the presence of heparin, besides these diffraction peaks of CaCO 3 calcite crystal, other peaks corresponding to (110), (112), ( 114) and (300) phases of CaCO 3 spherical vaterite crystal also appear, further confirming the coexistence of CaCO 3 calcite crystal and spherical vaterite crystal. The composition, structure and morphology of the CaCO 3 particles obtained in the presence of heparin are consistent with those of the previous report, 23 indicating that heparin has been entrapped into the particles. The content of heparin in CCPs-HP is 2.9% (w/w) determined by the toluidine blue assay.…”

“…The previous study indicated that it was the presence of heparin in the nucleation reaction of Ca 2+ and CO 3 22 ions that caused the morphology, size and phase purity of CCPs-HP different from those of pure CaCO 3 particles. 23 Thus, it seems reasonable to assume that the high-density COO 2 and HSO 3 2 group along the heparin backbone would also provide nucleation sites for hydroxyapatite through Ca 2+ ion accumulation. To further support this hypothesis, a fluorescence-labeling assay was carried out, in which CaCO 3 particles containing FITC-labeled heparin were used as the original materials.…”

“…The fabrication of CaCO 3 particles in the presence of heparin or FITC-labeled heparin was performed following a previous report. 23 In brief, 100 mg of heparin sodium was completely dissolved in 100 mL of 0.5 M calcium nitrate solution in a beaker under magnetic agitation (y600 rpm), into which an equal volume of 0.5 M sodium carbonate solution in another beaker was rapidly poured at room temperature. The final concentration of heparin was 0.5 mg mL 21 .…”

Macroscale preparation of nanosized calcium carbonate by exploiting biogas slurry synchronous metathesis encapsulation method

“…16,36,37 Most importantly, polymers can effectively inhibit inorganic particle growth and agglomeration, so as to overcome the disadvantages of uneven dispersion and easy aggregation of NCC in organic/ inorganic composites. 4 Liu et al 38 studied that humic acid was added into the Ca(OH) 2 carbonization system to control the morphology of CaCO 3 and well synthesize CaCO 3 with a specific surface area larger than 50 m 2 g À1 .…”

Morphological control of zinc tricarbohydrazide perchlorate crystals: Theoretical and experimental study

“…A fine crystal-morphology plays an important role in the safety and stability of a material [5][6][7]. Methods for controlling crystal-morphology can therefore be used to regulate nucleation and crystal growth during the crystallization process to increase the production and use of security of energetic materials, and improve their energy output performances [8][9][10][11][12].…”