Study on preparation of a novel adriamycin-loaded ultrasound microbubble and release characteristics in vitro / 中华超声影像学杂志

ABSTRACT

Objective To combine the active poly lactic co-glycolic acid (PLGA) nanosperes with adriamycin in side (ADM-NP) on the surface of ultrasound micrbubbles in covalent bonding and to prepare a novel drug-loading ultrasound micrbubble,and observe the physicochemical property.To quantify drug encapsulation efficiency and drug-loading amounts and drug-release properties in vitro and the effect of tumor imaging.Methods ADM-NP were prepared with double emulsification method,The surface carboxyl of ADM-NP was activated with carbodiimide method.Amino ultrasound microbubbles (MB-NH2) were prepared with mechanical shaking.The carboxyl of ADM-NP and the MB-NH2 could take place condensation reaction under a certain condition.Light microscope was used to observe the shape and distribution of the novel micrbubble.High performance liquid chromatography (HPLC) was used to quantify drug encapsulation efficiency and drug loading amounts.This novel microbubbles were put in 2 dialysis bag to observe the releasing properties of ADM in vitro,and one of the bag was using low frequency ultrasound irradiation for 120 s.The effect of tumor imaging using this novel microbubble was observed.Results After 48 hours,a number of ADM-NP attacted to the MB-NH2 like a gar land.Determination of entrapment efficiency and drug loading of it by HPLC weare (86.11 ± 6.76)％ and (8.71 ± 0.46)％.The sustained release in vitro can last for more than 48 hours.More than 90％ of ADM encapsulated in the 2 groups was sustained released for 48 hours.And the release characteristics of the 2 groups in vitro was in accord with Higuchi equation,and no difference was observed in the 2 groups (P ＞0.05).The tumor showed typical enhancement pattems of quick wash-in and quick wash-out.Conclusions To combine the nanospheres to the surface of microbubbles with covalent bonding,it could prepare a novel efficient drug-loading microbubbles for a original technique of ultrasound-targeted microbubble destruction(UTMD).