Preparation of hematoporphyrin-loaded PLGA ultrasound microbubble and optimization of formulation / 中华超声影像学杂志

ABSTRACT

Objective To optimize the formulation of a new kind of ultrasound contrast agents carrying the sensitizer of hematoporphyrin(HP)with[Poly(lactic-co-glycolic acid),PLGA]for material.Methods The technique of double emulsion was applied to produce HP loaded PLGA ultrasound microbubbles,which was optimized through orthogonal test using encapsulation efficiency for the detected index.Then morphology and distribution of HP-PLGA microbubbles were observed through light microscope and scaning electron microscope.The size,Zeta potential and the properties of releasing behavior and ultrasound imaging in vitro of Hp-PLGA contrast agents were detected.Results The optimization parameters were picked out as 10 mg/ml for concentration of HP,40 mg for PLGA,and 1/5 for volume ratio of water inside to dichloromethane.The optimized HP-PLGA contrast agents were spheric with the mean size of 602.3 nm,and Zeta potentiaI of-(17.1±1.6)mV.The drug loading and encapsulation efficiency of HP-PLGA were(2.15±0.15)%and(63.5±2.6)%,respectively.And the releasing behavior of HP-PLGA contrast agents in vitro was that after an obvious release of about 35.1%in former 24 h,there were 86.5%HP-PLGA released within 14 days.The ultrasound imaging of HP-PLGA could be enhanced obviously in vitro.Conclusions The self-made HP-PLGA ultrasound microbubble might be a useful tool for delivering sensitizer and thus provide a novel strategy for sonodynamic therapy on tumor.