Covalent Organic Framework-Incorporated Nanofibrous Membrane as an Intelligent Platform for Wound Dressing

Abstract

Covalent organic frameworks (COFs) possess fascinating features that have sparked increasing interest as drug carriers in biomedical applications. However, the promising properties of COFs in wound healing have rarely been reported. Herein, a facile one-pot method is reported to prepare a curcumin-loaded COF (CUR@COF) by the condensation reaction and the Schiff base reaction and to further incorporate CUR@COF into polycaprolactone (PCL) nanofibrous membranes (CUR@COF/PCL NFMs) through electrospinning to develop a pH-triggered drug release platform for wound dressing. CUR@COF has a high CUR loading capacity of 27.68%, and CUR@COF/PCL NFMs exhibit increased thermal stability, improved mechanical properties, good biocompatibility, and enhanced antibacterial and antioxidant activities. More importantly, CUR@COF-based membranes show a pH-responsive CUR release profile by protonation under acidic conditions, suggesting the promotion of CUR release from membranes under an acidic extracellular microenvironment. The histopathological analysis and immunofluorescence staining of an in vivo skin defect model indicate that CUR@COF/PCL NFMs can accelerate wound healing and skin regeneration by reducing the expression of inflammatory factors (TNF-α) and enhancing the expression of angiogenesis (VEGF). This work provides a new strategy by employing COF-based drug-encapsulated nanocomposites for wound dressing applications.

Porous organic polymers for drug delivery: hierarchical pore structures, variable morphologies, and biological properties

“…A current hot topic is the combination of different POPs and electrospun fibers to endow fiber membranes with different properties. Zou et al 128 encapsulated curcumin (CUR) in COFs (CUR@COF) and electrospun it into polycaprolactone (PCL) nanofibrous membranes (CUR@COF/PCL NFMs). The experimental results showed that the specific surface area and porosity of the TAPB-DMTA-COFs were larger than those of the CUR@COF.…”

Metalated covalent organic frameworks: from synthetic strategies to diverse applications

“…848 Additionally, due to their porosity, COFs can be loaded with high levels of antibiotics to provide slow and sustained antibiotic release. [849][850][851] Furthermore, photosensitive COFs induce the generation of reactive oxygen species (including 1 O 2 , O 2 À , OH, etc.) under light, causing the oxidation of bacterial membrane structures and killing bacteria.…”

Covalent Organic Frameworks (COFs) as Multi-Target Multifunctional Frameworks

“…More crucially, CUR@COF-based membranes exhibit a pH-responsive CUR release profile through protonation under acidic conditions, implying that an acidic extracellular milieu promotes CUR release from membranes. CUR@COF/PCL NFMs can speed up wound healing and skin regeneration by reducing the expression of inflammatory factors (TNF-a) and increasing the expression of angiogenesis according to histopathological examination and immunofluorescence labeling of an in vivo skin defect model (VEGF) [ 152 ].…”