While graphene can claim the title of science's sexiest wonder material, other substances called metal-organic-frameworks or MOFs, have been quietly changing the world while their single-atom-thick cousin hogs the spotlight. Now, researchers at Northwestern University (NU) have used MOFs to extend the speed and duration of ibuprofen, a result that could mean better pain relief for all of us.
MOFs are structures built from a mesh of metals and organic molecules. By changing the components of an MOF, you can change its function. One of the more useful features of MOFs is that they pack large surface areas into a small form factors. Those surface areas can be used to trap various molecules. So MOFs have been used to grab water out of dry air, trap contaminants in drinking water, create a fabric that neutralizes chemical-weapon attacks, and build a highly sensitive chemical sniffing system.
In this most recent use of the materials, the NU researchers created a MOF out of cyclodextrin (sugar molecules arranged in a ring) and alkali metal cations, and used it to trap molecules of the anti-inflammatory and pain-relieving drug ibuprofen.
"Although MOFs have been frequently discussed as potential drug-delivery vehicles, very few instances of in vivo studies involving MOFs have been reported to date," say the researchers.
In tests conducted on mice, the ibuprofen trapped in the MOF reached the bloodstream within 10 to 20 minutes, which is about the same time it takes for ibuprofen salts – which are found in liquid gel preparations – to work. But, the researchers found that the drug lasted twice as long. In the dosages given to the mice, its half-life clocked in at two hours versus the usual half-life of one hour for ibuprofen salts.
"As for the reason why the MOF works, we aren't sure at this stage," lead researcher Karel Hartlieb told New Atlas. "But the cyclodextrins upon which the MOF is built are known to act as agents to increase bioavailability of drugs." Hartlieb also told us that it is very easy to prepare ibuprofen/MOF constructs and that once produced, the formulation is very stable.
The NU team is hoping to take its findings to the next level and develop the process for the commercial delivery of ibuprofen as well as other drugs. "We used ibuprofen as a model compound, but it is possible to load a variety of other drugs within MOF, and in the future we'd like to collaborate with the pharmaceutical industry to explore the potential of MOF for formulation and drug-delivery technologies," Karel said.
The work has been reported in Molecular Pharmaceutics.
In the following video, UC Berkeley's Omar Yaghi – who was not involved in the research, but who pioneered MOFs about 20 years ago – talks about the compounds and his work creating a device that uses them to harvest water from very dry air.