Seredin Pavel, Goloshchapov Dmitry, Buylov Nikita, Kashkarov Vladimir, Emelyanova Anna, Eremeev Konstantin, Ippolitov Yuri
Solid State Physics and Nanostructures Department, Voronezh State University, Universitetskaya Pl. 1, 394018 Voronezh, Russia.
Scientific and Educational Center, Nanomaterials and Nanotechnologies, Ural Federal University, Lenin Ave 51, 620002 Yekaterinburg, Russia.
Nanomaterials (Basel). 2022 Dec 15;12(24):4453. doi: 10.3390/nano12244453.
In our paper, we discuss the results of a comprehensive structural-spectroscopic and microscopic analysis of non-stoichiometric nanocrystalline hydroxyapatite (CHAp) with low carbonate anion content and biomimetic hybrid nanomaterials produced on its basis. It was shown that hydroxyapatite nanocrystals synthesized by chemical precipitation and biogenic calcium source mimic the properties of biogenic apatite and also have a morphological organization of "core-shell" type. The "core" of the CHAp nanocrystal is characterized by an overabundance of calcium Ca/P~1.9. Thus "a shell" with thickness of ~3-5 nm is formed from intermediate apatite-like phases where the most probable are octocalcium phosphate, dicalcium phosphate dihydrate and tricalcium phosphate. The multimode model of the Raman profile of samples CHAp and biomimetic composites for spectral region 900-1100 cm proposed in our work has allowed to allocate precise contribution of B-type carbonate substitution, taking into account the presence on a surface of "core" HAp nanocrystal of various third-party intermediate apatite-like phases. The calibration function constructed on the basis of the described model makes it possible to reliably determine small concentrations of carbonate in the structure of hydroxyapatite with the application of Raman express method of diagnostics. The results of our work can inspire researchers to study the processes of induced biomineralization in mineralized tissues of the human body, using non-destructive methods of control with simultaneous analysis of chemical bonding, as well as determining the role of impurity atoms in the functions exhibited by biotissue.
在我们的论文中，我们讨论了对低碳酸根阴离子含量的非化学计量纳米晶羟基磷灰石（CHAp）以及在此基础上制备的仿生杂化纳米材料进行综合结构光谱和显微镜分析的结果。结果表明，通过化学沉淀法和生物源钙源合成的羟基磷灰石纳米晶体模拟了生物源磷灰石的性质，并且具有“核壳”型的形态组织。CHAp纳米晶体的“核”的特征是钙过量，Ca/P约为1.9。因此，由中间类磷灰石相形成了厚度约为3 - 5 nm的“壳”，其中最可能的是磷酸八钙、二水磷酸二钙和磷酸三钙。我们工作中提出的针对900 - 1100 cm光谱区域的CHAp样品和仿生复合材料拉曼光谱的多模模型，考虑到“核”HAp纳米晶体表面存在各种第三方中间类磷灰石相，能够精确确定B型碳酸盐取代的贡献。基于所描述模型构建校准函数，使得应用拉曼快速诊断方法能够可靠地测定羟基磷灰石结构中少量的碳酸盐。我们的工作结果能够激发研究人员利用无损控制方法同时分析化学键合以及确定杂质原子在生物组织所展现功能中的作用，来研究人体矿化组织中的诱导生物矿化过程。
