Synthesis and application of MOFs

Lead Research Organisation: University of St Andrews
Department Name: Chemistry

Abstract

The project is to develop the synthesis and formulation of metal-organic frameworks (MOFs), and to fully characterise any material that are prepared using TEM, XRD and other important techniques. The overall goal of the project is to understand how MOFs can be prepared so that they can be formulated as articles that can be further used in commercial applications. In particular the student will look at preparing polymer/MOF composites which are specifically designed for use in medical applications.



Training The student will be trained in the synthesis and manufacture of MOFs, their formulations as coatings and will be trained in several different characterisation techniques: X-ray diffraction and electron microscopy being the two most important.

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/N509759/1 30/09/2016 29/09/2021
1794900 Studentship EP/N509759/1 30/09/2016 23/04/2020 Simon Vornholt
 
Description Metal-organic frameworks are a new exciting class of porous materials, often with extremely high internal surface area and porosity, often good crystallinity, and thermal as well as thermal stability. Hence, these materials have a high potential for future applications such as catalysis, sensing, gas storage and adsorption, and medical applications. Storage and delivery of biologically active gases for medical applications are amongst the most exciting potential uses for MOFs. Ni-CPO-27 (a 2,5-dihydroxytherephthalate framework with nickel as its nodes) shows exceptional storage and release properties for nitric oxide (NO), a gas that exhibits anti-bacterial, anti-thrombotic and wound healing properties when delivered in low concentrations. Employing MOFs as storage/release agents permits these advantageous properties to be harnessed by controllably delivering low concentrations of the gas, thus avoiding the toxicity associated with high concentrations. NO-releasing MOFs are therefore potentially very suitable for incorporation into medical devices such as catheters, which are a major cause of Healthcare Associated Infections. Pre NO-loaded MOFs and their composites can be exposed to a moist atmosphere, which then leads to the release of NO while the MOF or composite returns to its conformation where water is adsorped.
Through my funding, I was able to optimise the synthesis, evaluate, and understand the performance of metal-organic framework composites that can be used as antibacterial catheter coating. The synthesis was optimised by a thickness study where different loading contents of the MOF inside the polymer matrix, and different thicknesses of each composite film, yielded different uptake levels of NO. It was found that the best loading content was 10 wt% MOF at 100 micrometer thickness, performed best. This is important for future upscale as thinner coatings and lower loading levels are desired for optimal use of resources. I was able to synthesise single crystals of CPO-27-Ni (not previously reported in the literature) to apply a more mechanistic and fundamental study of the NO transport. This was also evaluated in the final composite; my research has given a better insight into the kinetics of nitric oxide. By applying cutting-edge scanning microscopy techniques such as focused ion beam 3D reconstructions I could visualise that lower MOF loadings yield a more discrete agglomeration in the polymer matrix which explains why lower levels of MOF loading in the polymer gave a better NO release kinetic. Furthermore, I synthesised new MOFs through a mixed linker approach that have exciting potential to be taken further in a drug loading approach.
Three further manuscripts are currently in preparation
Exploitation Route My work has given insight into the fundamentals and the kinetics of the exciting use of MOF composite materials for antibacterial coatings and their use as medical devices. These fundamental steps are necessary for potential cost analyses, prototyping, and clinical trials. Furthermore, the new synthesis approach of making starting materials translates to a cost reduction of 94%. The new metal-organic frameworks that I have synthesised show interesting inherent flexibility which is important for drug loading or hosting of guest molecules (gas adsorption, sequestration). Furthermore, the single crystals of CPO-27-Ni that I made could be used for in-situ gas cell experiments at Diamond (Synchrotron). This analysis required crystals of excellent quality and the appropriate size and these experiments are crucial for a fundamental understanding of the gas adsorption in specific systems. It is planned to apply for further proposals at Diamond with these single crystals.
Sectors Chemicals,Healthcare,Manufacturing, including Industrial Biotechology

 
Description Healthcare-associated infections (HAI) are a huge problem for society, globally. Four million patients are affected each year (numbers for the EU alone); direct consequences are 37,000 fatalities and 1 billion extra cost for the healthcare sector. My research focuses on the potential treatment of urinary tract infections; a big portion of HAI (21%). The current treatment of HAI and especially catheter-associated urinary tract infections is the administration of antibiotics, which accelerated the build up of bacterial resistances. My key findings represent a stepping stone to the potential prototyping of a new type of antibacterial catheter coating. Which have the potential of preventing healthcare-associated infections in the future.
First Year Of Impact 2016
Sector Healthcare,Manufacturing, including Industrial Biotechology
Impact Types Societal,Economic

 
Description Collaboration with the University of Montpellier (Prof Guillaume Maurin) to study the compatibilty of chosen metal-organic frameworks with a polyurethane matrix. 
Organisation University of Montpellier
Country France 
Sector Academic/University 
PI Contribution I provided the science case.
Collaborator Contribution The collaborator's contributions were the computational calculations.
Impact Manuscript is in preparation.
Start Year 2019