Development of PVA-based microsphere as a potential embolization agent.

The development of tissue adhesive embolization microspheres with imaging ability is one of the important methods to improve the efficacy of interventional embolization. This study reported the synthesis of iodine (I)-polyvinyl alcohol (PVA)@polydopamine (PDA) microspheres to achieve the computed tomography image, drug loading and controlled release, and the enhanced embolization of liver portal vein. The I-PVA@PDA microspheres with a diameter of 147.9 μm showed an excellent computed tomography imaging ability. Moreover, the introduction of PDA endowed the I-PVA@PDA microspheres with tissue adhesive ability and therefore the in vivo embolization effect was improved. The in vivo embolization results showed that focal necrosis of hepatocytes with necrotic cell fragments and inflammatory cell infiltration was observed in the liver tissue, proving that the I-PVA@PDA microspheres have an enhanced embolization effect than PVA particles. The I-PVA@PDA microspheres were further used to deliver and release of chemotherapeutic drugs (5-fluorouracil), which displayed an initial fast release (release amount: 29.74%) in the first 24 h and then a sustained release of 34.48% within 72 h. Moreover, as a universal platform, the PVA@PDA microspheres could combine with other imaging agents like Bi2S3, thus holding a great potential in the interventional treatment of different diseases.