甲氨蝶呤/层状双金属氢氧化物的粒径调控及缓释性能研究  

Controllable Synthesis and Release Properties of Methotrexatum/Layered Double Hydroxide Compounds

作　　者：齐凤林[1] 李淑萍[1] 张晓晴[1] 

机构地区：[1]江苏省生物功能材料重点实验室、南京师范大学化学与材料科学学院,南京210097

出　　处：《化学学报》2012年第20期2162-2168,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(No.21073093);高等学校博士点专项科研基金(No.20103207120006);江苏高校优势学科建设工程资助~~

摘　　要：在乙醇-水混合体系中,以氨水为沉淀剂共沉淀合成了甲氨蝶呤/层状双金属氢氧化物(MTX/LDH)纳米复合物,首次采用控制沉淀剂滴加速率的方式来调控其粒径.利用X-射线衍射(XRD)、透射电镜(TEM)和红外光谱(FT-IR)等表征手段,对其结构及形貌进行了表征.研究表明:MTX分子以单层倾斜方式插入LDH层间,随着滴加速率不同,MTX在层间的倾斜角度发生了变化;沉淀剂滴加速率对产物的结晶度、粒径和层间排列方式都有影响,当沉淀剂滴加速率为0.100 mL/s时,得到的MTX/LDH纳米复合物的结晶度最高,粒径最大.在磷酸缓冲液中考察了不同粒径MTX/LDH纳米复合物的缓释性能,结果表明:小粒径的MTX/LDH纳米复合物的载药量要高于大粒径的;当MTX阴离子在层间的倾斜角度相似时,粒径小的粒子释放速率较慢,缓释效果优于粒径大的.尤为重要的是我们探索出一条保证复合物阴离子在层间的倾斜角度相似的情况下,制备不同粒径纳米复合物的新途径.The methotrexatum/layered double hydroxide （MTX/LDH） compounds with different particle sizes were prepared by controlling the dropping speed of precipitator, using the coprecipitation method in alcohol-water solvent and NH3·H2O as precipitator. The influence of the dropping speed of precipitator on the structure and morphologies of MTX/LDHs was systematically characterized by X-ray diffraction （XRD）, transmission electron micrograph （TEM） and fourier transform infrared spectroscopy （FT-IR）. The results indicated that MTX anions were intercalated into the LDH interlayers with a declined monolayer and the angle of inclination changed with the variation of the dropping speed of precipitator. Furthermore, the dropping speed of precipitator affected the crystallinity and particle size as well as arrangement way of MTX in LDH interlayers, when the dropping speed is 0.100 mL/s, the products have the highest crystallinity and the maximum diameter. All the MTX/LDHs particles exhibited hexagonal platelet morphology with round corner and good monodispersity. At last, the release properties of MTX/LDHs with different particle sizes were studied in phosphate buffer. The results indicated that the smaller nanoparticles have higher drug-loading capacity than those of the larger ones and when the angles of inclination keep almost constant, the smaller nanoparticles have the longer release time than those of the larger ones. In addition, four kinetic models （first-order equation, Higuchi equation, Bhaskar equation and Ritger-Peppas equation） were used to study the release kinetics of MTX from the LDH interlayers, and it was found that the mechanism for drug release can be well described by the Ritger-Peppas equation, revealing that the release mechanism of MTX/LDH belongs to drug diffusion and Fickian diffusion is the rate limiting step. First of all, we have explored a new way to synthesize LDH compounds with different particle size in the guarantee of the angles of inclination of anions in interlayer keepin

关 键 词：纳米粒子 层状化合物 缓释性能 沉淀剂滴加速率 甲氨蝶呤 

分 类 号：TB383.1[一般工业技术—材料科学与工程]