I-125-AIBZM Nanoliposomes Targeting Brain as Imaging Agents

The aim of this study is to develop a blood brain barrier permeable nano-liposome drug delivery system that significantly up-regulates the brain uptake of (S)-5-I-125-N-(1-ethyl-2-pyrrolidinyl) methyl-4-amine-2-methoxy-benzamide(I-125-AIBZM) as an imaging agent. Both I-125-AIBZM-nanoliposome (I-125-AIBZM-L) and I-125-AIBZM-lactoferrin-nanoliposome (I-125-AIBZM-Lf-L) were prepared by the ammonium sulfate gradient method with a. small particle size(ca. 100 nm) and a narrow size distribution pattern. The encapsulation efficiencies of I-125-AIBZM-L and I-125-AIBZM-Lf-L were measured as 39% and 35%, respectively. In vivo fluorescence imaging results showed that DIR-Lf-L was successfully delivered drug into the brain. The pharmacokinetic experiments in rats indicated that the blood circulation times of I-125-AIBZM-L and I-125-AIBZM-Lf-L were substantially longer than that of small molecular I-125-AIBZM. Amount of intracerebral I-125-AIBZM delivered by I-125-AIBZM-L was significantly lower than that of I-125-AIBZM-Lf-L(P<0.01) but remarkably higher than that of I-125-AIBZM(P<0.01). In conclusion, I-125-AIBZM-Lf-L nano-liposome drug delivery system can increase the brain uptake of imaging agent I-125-AIBZM.