Iodine Immobilized UiO-66-NH2 Metal-Organic Framework as an Effective Antibacterial Additive for Poly(ε-caprolactone)

Abstract

Iodine has been widely used as an effective disinfectant with broad-spectrum antimicrobial potency. However, the application of iodine in an antibacterial polymer remains challenging due to its volatile nature and poor solubility. Herein, iodine immobilized UiO-66-NH2 metal-organic framework (MOF) (UiO66@I2) with a high loading capacity was synthesized and used as an effective antibacterial additive for poly(ε-caprolactone) (PCL). An orthogonal design approach was used to achieve the optimal experiments’ conditions in iodine adsorption. UiO66@I2 nanoparticles were added to the PCL matrix under ultrasonic vibration and evaporated the solvent to get a polymer membrane. The composites were characterized by SEM, XRD, FTIR, and static contact angle analysis. UiO-66-NH2 nanoparticles have a high iodine loading capacity, up to 18 wt.%. The concentration of iodine is the most important factor in iodine adsorption. Adding 0.5 wt.% or 1.0 wt.% (equivalent iodine content) of UiO66@I2 to the PCL matrix had no influence on the structure of PCL but reduces the static water angle. The PCL composites showed strong antibacterial activities against Staphylococcus aureus and Escherichia coli. In contrast, the same content of free iodine/PCL composites had no antibacterial activity. The difference in the antibacterial performance was due to the different iodine contents in the polymer composites. It was found that MOF nanoparticles could retain most of the iodine during the sample preparation and storage, while there was few iodine left in the free iodine/PCL composites. This study offers a common and simple way to immobilize iodine and prepare antibacterial polymers with low antiseptic content that would reduce the influence of an additive on polymers’ physical properties.

Zirconium-Based MOFs and Their Biodegradable Polymer Composites for Controlled and Sustainable Delivery of Herbicides

“…Diffraction peaks at 22 and 25° (2Θ) correspond to the crystallinity of the polymer structure for the PCL composite of IS-MCPA@UiO-66 (referred to as PCL@IS-MCPA@UiO-66). 50 …”

“…PXRD patterns (Figure ) of the composites show characteristic peaks of the MOFs, confirming that no phase changes occurred during the preparation of the composites. Diffraction peaks at 22 and 25° (2Θ) correspond to the crystallinity of the polymer structure for the PCL composite of IS-MCPA@UiO-66 (referred to as PCL@IS-MCPA@UiO-66) …”

“…Diffraction peaks at 22 and 25°(2Θ) correspond to the crystallinity of the polymer structure for the PCL composite of IS-MCPA@UiO-66 (referred to as PCL@IS-MCPA@UiO-66). 50 SEM imaging of the composites showed a scattered distribution of particulate microcrystalline MOFs in the polymer matrix (Figure 5). This is further supported by the elemental mapping using EDX (Figure S7) which shows the Zr is well-dispersed across the composites.…”

Optimization of Extraction Conditions of Carotenoids from Dunaliella parva by Response Surface Methodology

“…With the progress of methodology, many advanced optimization methods such as orthogonal design and response surface methodology (RSM) emerged. An orthogonal design was used to obtain the optimal experimental conditions in iodine adsorption [ 49 ]. An orthogonal design was used to optimize light irradiance and the ratio of photoperiods and LEDs in order to increase the photosynthetic capacity and growth of cucumber seedlings by LED illumination [ 50 ].…”

Binding Materials for MOF Monolith Shaping Processes: A Review towards Real Life Application

“…Metal-organic frameworks (MOFs) are organic-inorganic hybrid crystalline microporous materials [1]. They consist of positively charged metal ions interconnected with organic ligands [2]. This regular array of metal ions can therefore be formed as a network with up to three dimensions [3].…”