目的:研制一种新型医用口服磁共振胃肠造影剂,其磁性及造影效果均强于用纳米磁性材料制成的超顺磁性造影剂.方法:根据磁学理论讨论造影剂中磁粒的悬浮稳定性、指出磁粒的尺寸是决定其稳定性的主要因素.用微米级Fe3O4微粒作为磁性粒子、羧甲基纤维素钠作表面活性剂、去离子水作基液,在制备过程中加入少量的非磁性纳米α-Fe2O3微粒.研究了加入不同量的α-Fe2O3微粒对造影剂稳定性的影响.并且对该造影剂进行了稳定性测试,以及活体磁共振加权像实验.结果:加入1 mg/1000 mL的纳米α-Fe2O3,造影剂可达到稳定.该造影剂可清晰勾画胃肠道,对胃肠道病变的诊断有较高的临床价值.结论:本制备方法可增强造影剂的稳定性,且工艺简单；同时微米磁粒的磁性大于纳米磁粒,造影效果明显提高.该制备方法对其它混悬液体系同样适用.%Objective: To prepare a new Magnetic Resonance Imaging (MRI) negative contrast agent which have high magnetic and a good contrast effective. Methods: Based on superparamagnetic theory the sedimentation stability of the contrast agent is discussed, and the result shows that the size of the particles is the major factor. With Fe3O4 as the major materials, sodium carboxymethylcellulose as surfactant, de-ionized water as a based liquid prepared the Magnetic Resonance Imaging contrast agent, and little nanoscale α-Fe2 O3 particles are added during preparation. This paper studies the effect of α-Fe2 O3 of different concentration on MRI. The contrast agent is selected for the stability and MR imaging contrast test. Results: The agent is stable after adding in 1 mg/1000 mL of α-Fe2 O3 .It could display gastrointestinal clearly. This contrast agent is of high value in clinical practice to diagnose for gastrointestinal. Conclusions: The experiments show that the sedimentation stability of the contrast agent can be greatly improved by adding little nanoscale α-Fe2O3 particles. The magnetic of the micron magnetic particles is higher than the nanoscale particles' s, and the contrast effective for the contrast agent with the micron magnetic particles is better than the nanoscale particles' s. Meanwhile, the method is suitable for other suspension system.
展开▼
