At a Glance
Metal-organic frameworks (MOFs) are solid state catalysts which can be tuned to successfully catalyze the generation of Nitric Oxide (NO) from bioavailable NO donors, S-nitrosothiols (RSNOs). The incorporation of MOFs into biomedical devices presents an interesting opportunity to counter device fouling based on their ability to facilitate sustained NO generation and thereby mimic the natural function of healthy cells.
MOFs are robust materials and can withstand incorporation onto a variety of secondary supports; towards this end, researchers at Colorado State University have developed composite MOF/polymeric materials which demonstrate catalytic NO generation from bioavailable RSNOs.
MOFs can be incorporated into polymeric matrices and fabricated into biomedical devices through an extrusion process without loss of structural integrity or diminished activity towards NO generation. In addition, cellulose is a particularly advantageous material for use as a secondary support for MOF growth. As such, an efficient method has been developed to adhere MOFs directly onto cotton surfaces and maintain catalytic function towards NO release. The successful development of MOF composite materials using synthetic and naturally occurring polymers as secondary supports has inspired usage in applications for antimicrobial catheter tubing and as wound healing dressings.
Metal-organic frameworks (MOFs) are a class of materials whose synthetic versatility and porous crystalline frameworks have propagated their exploration across the spectrum of materials chemistry including gas storage, chromatography, catalysis, and, most recently, biomedicine. However, realistic applications of MOFs have been inhibited primarily due to a lack of thermal stability as well as the uncontrollable release of incorporated payloads, such as hydrogen for fuel cells and therapeutic molecules when used as drug delivery vehicles.
In biological applications, site localized effects are critical towards the ultimate success of materials. Thus, the dispersion of fine powders consisting of MOFs are typically undesirable. As such, the integration of MOFs with solid supports can lead to the potential use of MOFs in previously unrecognized applications. Composite MOF materials, also known as mixed matrix membranes, may be prepared by dispersing MOF particles, such as CuBTC, into polymeric matrices and may facilitate the use towards gas separations and catalysis. The incorporation of these inorganic frameworks into materials creates a symbiotic system allowing enhanced properties of both systems involved. However, these systems have several shortcomings, including leaching.
Multifunctional MOF materials that can bridge the gap between heterogeneous catalysis and drug delivery can revolutionize the development of biomedical devices. Traditionally the use of MOFs as drug delivery vehicles relies on the subsequent incorporation of therapeutics into the pore space. While this has been explored as a viable method for delivery therapeutics it remains limited by the often uncontrollable release of therapeutics, the restriction that only one mode of therapeutic action can be achieved, and the supply of therapeutics is thus restricted to the amount that can be incorporated into the MOF.
- Overcomes biofouling
- Demonstrates antimicrobial activity (wound healing applications)
- Therapeutic agents can be incorporated in conjunction with the MOFs (e.g. anti-thrombotic agents, anti-inflammatory agents, anesthetics, anti-coagulants, growth factors, etc.)
- Compounds can form both symmetric and asymmetric structures having various shapes, porosities, sizes and rigidities
- Materials can be used to treat clinically relevant disease or complications
- Coatings and material compositions for fabricating medical devices
- Coatings on medical equipment (e.g. tables, IV poles, other surfaces) prone to bacteria or viruses
- External applications include bandages (e.g. wound healing) and catheters