运用X射线微区衍射、透射电镜、扫描电镜与能谱测试技术对淡水鲈鱼硬体组织的鳞片、牙齿、鳍骨、蝶骨和脊椎骨中无机矿物做了成分与结构方面的探究。结果表明硬体组织中的矿物相均为羟磷灰石,化学成分呈现缺Ca富P的特征。鳞片中羟磷灰石晶胞参数具有较大的变动范围a=0.941 8~0.947 7 nm,c=0.684 1~0.690 3 nm;骨骼中a=0.942 6~0.945 7 nm,c=0.687 3~0.688 7 nm;牙齿中a=0.946 3 nm,c=0.688 0 nm。晶粒尺寸达到纳米级别,计算结果为D_鳞=7.204~13.711 nm,D_骨=14.088~17.077 nm,D_牙=28.219 nm。结晶度由好到差的顺序为:牙齿→骨骼→鳞片。X射线衍射图表明,牙齿、鳞片和骨骼中羟磷灰石晶体均具有择优取向结晶特点,取向因子R计算结果表明硬体组织中羟磷灰石均趋向沿c轴择优取向生长。生物矿物结晶度及择优取向是组织功能和有机基质调控的结果。X射线微区衍射技术能无损、有效的获取生命微晶体的结构信息,适合生物矿物研究。
In this paper, crystallographic characteristics of inorganic mineral phase existing in scale, tooth and bone(fin, sphenoid, and backbone) of freshwater lateolabrax japonicus were investigated by means of X-ray micro diffractometry ( XRMD ) , transmission electron microscopy ( TEM ) , environmental scanning microscopy ( ESEM ) and energy dispersive spectrometry ( EDS ). Results show that the crystal phase in these hard tissues is sole hydroxylapatite (HAP) .The chemical composition characteristics of HAP is lack of Ca and rich in P.Refined lattice parameters of HAP show a wide range in scale (a=0. 941 8- 0. 947 7 nm and c=0. 684-0. 690 3 nm), in bone (a=0. 942 6-0. 945 7 nm and c= 0. 687 3-0. 688 7 nm)and in tooth (a = 0. 946 3 nm and c = 0. 688 0 nm).The coherent domain sizes are Dscale = 7. 204-13. 711 nm, Dboae= 14. 088-17. 077 nm and Dtooth = 28. 219 nm. From tooth to bone to scale it shows a sequence from good to poor in crystallinity. Those textural index R values indicate that all HAPs in hard tissues of lateolabrax japonicus have a preferring orientation along crystallographic c axis. The crystallinity and preferring orientation of HAP are designed by tissue function and controlled by organic matrix. X-ray micro diffractometry can well help to obtain valuable slructure information by ways of in-situ and non-destruction, and henee it is more suilable than powder diffraction in biomineral sludies.