ZIF@polymer monolith as small-caliber vascular prosthesis prototype based on controlled release of heparin and its application in sterilization

Abstract

A novel small-caliber vascular prosthesis prototype (SCVPs) with antibacterial application is proposed based on the controlled delivery of heparin from ZIF@polymer monolith. The traditional powdery small-caliber vascular prosthesis material has the disadvantages of difficult separation and easy agglomeration, which limits its applications. Heparin (HP)-loaded porous ZIF-8/Polymer (PEG, PVA, and PVP) monoliths were fabricated using a freeze-casting method in liquid nitrogen (− 196 ℃) for controlled heparin release and sterilization. The incorporation of ZIF-8/Polymer significantly improved the antibacterial performance of the samples, prolonged the slow-release time of heparin sodium, and also resulted in better mechanical properties. The samples synthesized at a heparin sodium concentration of 0.36 mg·mL⁻¹ exhibited good sustained release of heparin sodium when used as artificial antigenic matrix. Among these materials, the cured HP@ZIF-8 sample had a retarded release time of up to 15 h, with a cumulative release of 223.56 μg at 24 h. With PVA as the optimal polymer, heavy metal ions from the cured HP@ZIF-8 material can cause severe toxic damage to the internal structure of bacteria, interfere with bacterial metabolism, and thus show obvious antibacterial effects.