Study on the in vitro targeting and imaging performance of aptamer modified targeted ultrasound/photoacoustic dual-modality contrast agent / 中华超声影像学杂志

ABSTRACT

Objective To study the targeting ability of aptamer-modified PLGA nanoparticle encapsulated with gold nanorod and liquid perflurocarbon,and observe its mediated ultrasound/photoacoustic dual-modality imaging in vitro.Methods PLGA nanoparticle was prepared using double emulsion technique.Aptamer-modified PLGA nanoparticle was obtained by connecting,then PLGA nanoparticle was conjugated with MUC1 aptamer carbodiimide technique aimed to obtain aptamer-modified PLGA nanoparticle.Targeting ability of aptamer-modified PLGA nanoparticle to MCF-7 tumor cells in vitro was tested by fluorescence microscope.Besides,there were three control groups including PLGA nanoparticle group,aptamer group and HELA cell group.A commercial photoacoustic instrument was used to detect ultrasound/photoacoustic signal.Results A significant number of aptamer-modified PLGA nanoparticles gathered around the MCF-7 cells,however,the specific binding can not be observed in control groups.Both ultrasound and photoacoustic signal intensity of the aptamer-modified PLGA nanoparticles increased significantly when excited with laser.Conclusions The aptamer-modified PLGA nanoparticle was successfully prepared,and had superior targeting ability to MCF-7 cells,Morever,ultrasound/photoacoustic signal emitted the by nanoparticle increased significantly.These properties make the targeted nanoparticle a great potential to become a distinguished uhrasound/photoacoustic dual modality contrast agent,which lays good foundation for further targeted imaging application in vivo.