AeonClad the way to better drug, particle and device coatings

The plasma coating technology was developed by AeonClad's chief scientist, Professor Richard Timmons of the UTA and allows more efficient coverage of either drug particles or devices than other plasma deposition methods. The technique uses a pulsing method for maximising deposition of monomeric gases that polymerise on the surfaces of particles or objects in the reactor. "The plasma deposition starts with a monomer gas and then efficiently deposits thin polymeric films to any nearby surface​," said Prof. Timmons. "The new method is a breakthrough in nanotechnology coatings since it allows for ultra-thin, highly controllable functional surfaces with no 'pin-holes' that inhibit a device's intended function." ​ AeonClad was set-up with the help of life science venture capital firm Emergent Technologies Inc. (ETI) that focuses on funding early stage technology start-up companies. According to Dr Grant Gibson, vice president of market development at ETI, plasma deposition is a revolutionary way to coat very small particles that are difficult to do with traditional solvent based dipping or spraying techniques. Because the monomer gas permeates all the way round objects in the deposition chamber very efficient polymer coatings can be formed that do not contain 'pin-holes' or areas that are not covered by the coating. "The difficulty has been that no-one has been able to control the process precisely in the way that we do because the pulsing can disrupt the newly formed surface,"​ said Dr Gibson. "We've come up with a method to very efficiently and gently form that surface without shearing or ablating the surface away in subsequent cycles." ​ The technique has been dubbed radio-frequency pulsed plasma deposition and can be used to either create totally inert surfaces or surfaces with various different functionalities. Prof. Timmons group has used the technique to encapsulate crystalline drugs to control their release. The research, published in the International Journal of Pharmaceutics​​, used the technology to coat asprin (acetylsalicylic acid) crystals with polymerisable allyl alcohol. The results showed that the drug release rates could be finely controlled over a wide range by varying controlling the thickness, film composition and extent of cross-linking using the technique. In addition, the thin layer chromatography (TLC) experiments indicated that the technique was "particularly useful in terms of minimising the degradation of drug particles".​ The research group has also used the technique to coat expandable endovascular stents​ to reduce platelet adhesion and increase the biocompatibility of the device. The company believes that the technology can be expanded to prevent bacterial attachment to medical implants as well as controlling the release of drugs from drug eluting stents. Additionally, the technology has been used to produce protein affinity capture probes​ for use with MALDI (matrix assisted laser desorption / ionisation) MS (mass spectrometry) that allow the selective isolation of specific proteins from biological samples. "We believe that we are just scratching the surface with the potential applications that this technology can be used for and there may be dozens of other applications that we are yet to explore,"​ said Dr Gibson.