| dc.description.abstract | Metal-Organic Frameworks (MOFs), recognized for their high surface area and thermal stability, allow for diverse pore structures. This versatility has propelled their use in fields like gas storage and drug delivery. Particularly, aluminum-based MOFs, due to their inherent biocompatibility and the immune-enhancing properties of aluminum, have emerged as promising candidates for vaccine and protein delivery. Enzymes, prized for their high catalytic efficiency and specificity, are key in treating diverse diseases like metabolic deficiencies, cancers, and cardiovascular diseases. However, their effectiveness in oral administration is hampered by deactivation in harsh environments like the stomach′s acidity. This underscores the necessity of enzyme immobilization to boost their stability and practical application. The carrier shields enzymes or proteins from hydrolysis and aids their absorption via the intestinal microvessels, thus enabling their entry into the bloodstream and systemic circulation.
In our research, we synthesized the Al-based Metal-Organic Framework (MOF) NH2-MIL-53(Al) under mild aqueous conditions in 20 minutes. We also encapsulated the enzyme catalase (CAT) into the MOF, creating a biocomposite named CAT@NH2-MIL-53. Encapsulation was confirmed through Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) and isothermal nitrogen gas adsorption/desorption measurements. Our method preserved enzyme biological activity (kobs of 6.2×10-2 s-1) and provided proteolysis protection against proteases like Proteinase K. This activity which had a kobs of 2.49×10-2 s-1 surpasses our previous CAT@ZIF-90 research at least 2.5 fold times. Conversely, an elongated synthesis time reduces CAT activity, and an increased metal-to-linker synthetic ratio also diminishes activity.
Material tolerance assays show that under gastric conditions (pH 2 hydrochloric acid solution with pepsin), the NH2-MIL-53 structure remains stable even at pH 1.5 for 3 hours. The encapsulated catalase (CAT) retains its biological activity (kobs of 1.6×10-2 s-1). Notably, NH2-MIL-53 disintegrates in PBS buffer solution (Phosphate Buffered Saline, mimicking blood conditions) at pH 7.4, indicating potential enzyme release from NH2-MIL-53 in the bloodstream. | en_US |