Rey C, Renugopalakrishnan V, Collins B, Glimcher M J
Department of Orthopaedic Surgery, Harvard Medical School, Children's Hospital, Boston, Massachusetts 02115.
Calcif Tissue Int. 1991 Oct;49(4):251-8. doi: 10.1007/BF02556214.
The environment of CO3(2-) ions in the bone mineral of chickens of different ages and in bone fractions of different density have been investigated by resolution-enhanced Fourier Transform Infrared (FTIR) Spectroscopy. Three carbonate bands appear in the upsilon 2 CO3 domain at 878, 871, and 866 cm-1, which may be assigned to three different locations of the ion in the mineral: in monovalent anionic sites of the apatitic structure (878 cm-1), in trivalent anionic sites (871 cm-1), and in unstable location (866 cm-1) probably in perturbed regions of the crystals. The distribution of the carbonate ions among these locations was estimated by comparing the intensities of the corresponding FTIR spectral bands. The intensity ratio of the 878 and 871 cm-1 bands remains remarkably constant in whole bone as well as in the fractions obtained by density centrifugation. On the contrary, the intensity ratio of the 866 cm-1 to the 871 cm-1 band was found to vary directly and decreased with the age of the animal. In bone of the same age, the relative content of the unstable carbonate ion was found to be highest in the most abundant density centrifugation fraction. A resolution factor of the CO3(2-) band (CO3 RF) was calculated from the FTIR spectra which was shown to be very sensitive to the degree of crystallinity of the mineral. The crystallinity was found to improve rapidly with the age of the animal. The CO3 RF in the bone samples obtained by density centrifugation from bone of the same animal was found to be essentially constant.(ABSTRACT TRUNCATED AT 250 WORDS)
通过分辨率增强傅里叶变换红外光谱（FTIR）研究了不同年龄鸡的骨矿物质以及不同密度骨组分中碳酸根离子（CO₃²⁻）的环境。在υ₂ CO₃区域出现了878、871和866 cm⁻¹处的三个碳酸根吸收带，它们可能对应于该离子在矿物质中的三个不同位置：磷灰石结构的单价阴离子位点（878 cm⁻¹）、三价阴离子位点（871 cm⁻¹）以及可能在晶体受扰区域的不稳定位置（866 cm⁻¹）。通过比较相应FTIR光谱带的强度来估计碳酸根离子在这些位置之间的分布。878和871 cm⁻¹谱带的强度比在全骨以及密度离心得到的组分中都保持相当恒定。相反，发现866 cm⁻¹与871 cm⁻¹谱带的强度比随动物年龄直接变化且降低。在相同年龄的骨中，发现不稳定碳酸根离子的相对含量在最丰富的密度离心组分中最高。从FTIR光谱计算出碳酸根离子带的分辨率因子（CO₃ RF），结果表明它对矿物质的结晶度非常敏感。发现结晶度随动物年龄迅速提高。从同一动物的骨中通过密度离心获得的骨样品中的CO₃ RF基本恒定。（摘要截短于250字）
