Precise Temperature-Gradient Regulated Structure–Activity Relationship of PCN-224 as Bifunctional Nanocarriers

Abstract Metal–organic frameworks (MOFs) demonstrate considerable potential for biomedical applications. Due to their high porosity and photoactive porphyrin ligands, PCN-224 is considered an ideal drug delivery nanocarrier. However, the synthesis strategy for tailoring the application of PCN-224 in complex pathological diseases remains unclear. In this study, we investigated the structure–activity relationship of PCN-224 nanoparticles as bifunctional nanocarriers for osteoarthritis (OA) treatment under a precisely controlled temperature gradient. By tuning the temperatures, a series of PCN-224 nanoparticles with adjustable sizes were synthesized and their morphologies transitioned from a spindle-shaped to a spherical-shaped structure. The photoluminescence intensity of PCN-224 nanoparticles decreased as the synthesis temperatures increased. Using PCN-224 nanoparticles as aqueous lubricating additives, both the friction coefficient and wear volume were significantly reduced. Among the MOFs, PCN-224 (synthesized at 105 °C) exhibited excellent antifriction performances and acid-responsive drug release properties, demonstrating their promise as bifunctional OA treatment nanocarriers. Our work enhanced the understanding of the relationships between PCN-224 synthesis conditions and its physicochemical properties relationships, expanding their potential for multifunctional biomedical applications.