A Matter of Time?

Programming temporal shapeshifting Xiaobo Hu, Jing Zhou, Mohammad Vatankhah-Varnosfaderani, William F. M. Daniel, Qiaoxi Li, Aleksandr P. Zhushma, Andrey V. Dobrynin & Sergei S. Sheiko Nature Communications 7, Article number: 12919 doi:10.1038/ncomms12919

This is the answer to a number of everyday questions. For example:

  • When will England win the football world cup?
  • When will Boris Johnson make a fool of himself?
  • When will this article get to the point?

Well one of the holy grails of formulation technology is the ability to deliver an active ingredient to a specific target in a specific place at a specific time. For example, many pharmaceutical products need to survive the passage through the acidic environment in the human gut, seed coatings may need to release an active ingredient when germination starts, materials such as cement may need to flow for a certain period of time and then set.

Time is however not the primary controlling factor in the formulation technologies used at present. Instead there are often external triggers such as pH, light, or temperature which are intended to act at a certain time. However I came across an article recently however which could change this and make time a direct controlling factor. In a paper in Nature Communications, researchers from the Universities of North Carolina and Akron have published work that they entitled Programming Temporal Shapeshifting.

From this rather convoluted title, they have outlined how they can make materials in the form of dual network hydrogels which will change shape after a specific period of time from seconds up to hours. They do this by having covalent crosslinks in the first network which provide elastic energy storage and temporary hydrogen bonds in the second network which regulate the energy release rate. These hydrogen bonds can then be reversed, which means the rate and pathway of a shape transformation can be encoded in the material without any external stimulus or trigger.

Obviously this work is in its early stages but the potential to truly time the release of an active, or even multiple deliveries does bring tremendous opportunities not just in the pharmaceutical sector. So those days of searching for a pH, heat, or light trigger may be a thing of the past and it will really be just a matter of time…

David Calvert, October 2016

At iFormulate our clients we frequently ask us to find and evaluate new technologies of potential interest and use to them. We can do this by keeping abreast of a wide variety of technical developments. If you think we might be able to help you then contact us on info@iformulate.biz or take a look at our website www.iformulate.biz.