MOF-Enabled Nanocellulose Composite Threads for Sustained Antibacterial Drug Delivery and Minimally Invasive...

Minimally invasive thread lifting has emerged as an effective strategy for soft tissue repositioning and facial rejuvenation; however, currently used absorbable threads generally lack intrinsic antimicrobial functionality, which may increase the risk of postoperative infection. Here, we report a biodegradable antibacterial lifting thread based on a nanocellulose/MOF composite system. The thread was fabricated via a green wet-spinning strategy using carboxymethylated cellulose nanofibrils (CCNF, prepared with cellulose derived from Astragalus residue) and sodium alginate (SA) as the structural matrix, while tetracycline hydrochloride-loaded ZIF-8 nanoparticles were incorporated to provide sustained antibacterial activity. The resulting antibacterial CCNF/SA thread (AB-CCNF/SA) exhibited a uniform morphology and a tensile strength of 80 MPa. The porous ZIF-8 carriers enabled efficient drug loading and controlled release, providing effective antibacterial activity against Staphylococcus aureus and Escherichia coli. Meanwhile, the composite threads showed favorable biodegradability, with approximately 45% degradation within 56 days, together with excellent cytocompatibility as demonstrated by fibroblast viability above 90%. In vivo studies further revealed inflammatory responses comparable to those of commercial collagen threads, confirming the good biocompatibility of the system. Overall, this work establishes a strategy for integrating nanocellulose structural materials with MOF-enabled antibacterial drug delivery, providing a multifunctional platform that combines mechanical support, biodegradability, and sustained antibacterial activity for minimally invasive soft tissue lifting and related biomedical implant applications.