Experimental study of PLGA microparticles loaded with iron oxide labeling tendon stem cells in vitro

Abstract

Objective To prepare PLGA microparticles loaded with Iron oxide (PLGA/IO MPs) and explore their feasibility of the rat tendon stem cells (TSCs) labeled with the particles and the multimodal imaging of Ultrasonic (US)/Photoacoustic (PA)/Magnetic resonance (MR) in vitro. Methods The PLGA/IO MPs were prepared using double emulsification, and physical and chemical properties were tested and US/PA/MRI imaging was performed. The TSCs were labeled with PLGA/IO MPs, and transmission electron microscopy (TEM) and prussian blue staining were performed to test labeling effects, then the US, PA and MRI imaging of labeled TSCs were performed. Results The diameter and Zeta potential of prepared PLGA/IO MPs were (801.5±165.6)nm and (6.36±3.36)mV [the Zeta potential of microparticles which including poly-L-Lysine(PLL) was about (3.16±3.69)mV], respectively. PLGA/IO MPs could be imaged by US/PA/MRI multimodal imaging. After labeling, the PLGA/IO MPs were distributed in cytoplasm of labeled TSCs which could be imaged by US, PA, MRI simultaneously. Conclusions The TSCs can be labeled with PLGA/IO MPs effectively, and imaged by using multimodal US/PA/MRI imaging in vitro, which will lay foundation for noninvasive and multimodal tracking of transplanted TSCs in vivo. Key words: Ultrasonography; Iron oxide/PLGA microparticles; Tendon stem cells; Multimodal imaging; Photoacoustic imaging; Magnetic resonance imaging