A Brief History of Molecularly Imprinted Polymers: The Heart of Allergy Amulet’s Technology
If you’ve been following our blog for a while, you’ve probably heard us talk about our scientific approach to detecting food allergens: molecularly imprinted polymer (MIP) films. These films lie at the technological heart of the Allergy Amulet.
In a previous post, we covered the basics of how the technology works. Quick review: an MIP is a polymer (plastic) formed in the presence of target template molecules to create molecular molds. Once the templates are removed from our films, they leave behind trillions upon trillions of plastic molded “locks” that bind when in the presence of our molecular “keys.” In our films, these keys represent allergenic ingredients.
Today’s post looks at the history of MIP technology. While our science team has made considerable breakthroughs in the MIP field, we didn’t pull the foundation technology out of thin air. In fact, the body of work on MIPs dates back almost 100 years!
The first scientific mention of MIPs was back in 1931: a scientist named M. V. Polyakov discovered that when he made polymers out of silica in the presence of another molecule, the polymers would selectively absorb that molecule.
Some say the origins of MIP technology started with Jean Dickey at Cal Tech. He tried imprinting silica with organics back in 1949. The modern approach to imprinting began in Europe in the seventies and eighties with Klaus Mosbach in Sweden, Günter Wulff in Germany, Borje Sellegren in Amsterdam, and Karsten Haupt in France. These and other scientists developed many of the classic methods for creating imprinted polymers. Importantly, some studies found that in select circumstances, MIPs could imitate the functions of receptors, enzymes, and other biological molecules.
After these initial discoveries, scientists identified new applications throughout the 20th century—mostly in drug separation—and you can currently buy MIP resins from leading science manufacturers like Sigma Aldrich. Yet, as with any nascent technology, development progressed slowly. Only in the past ten years have MIPs finally hit their stride: nearly half of all MIP papers were written in the past decade. Over time, researchers have optimized the conditions and techniques for developing MIPs, which has expanded the types of molecules MIPs are capable of imprinting. This has dovetailed with advancements in nanotechnology and communications technology. For example, the nanomaterials we use in our sensors were prohibitively expensive ten years ago. With these advancements, diverse commercial applications of MIP technology are finally becoming a reality.
For a detection device, successfully imprinting an allergenic ingredient (or any other target) is only half the battle.
Why is that? Well, even if an MIP can selectively bind the target molecule, it does so on a nanoscopic scale—we would have no way of knowing that binding occurred. Creating an MIP sensor accordingly requires a system that can translate that imprinting into something comprehensible (what scientists would call a transducer). While there has been significant research into different types of transducers for MIPs, a common approach has been electrical conductivity: an easily measured property that is already widely used in sensor technology.
There are several methods that convert successful imprinting to an electrical response. Two of the most popular methods involve using either conductive polymers or combining the MIPs with conductive nanomaterials.
Some of the first successes in creating conductive MIPs originated with Dr. Joseph BelBruno: a world-renowned chemist, Dartmouth chemistry professor, and Scientific Advisor at Allergy Amulet. Dr. BelBruno’s research laid the foundation for developing conductive MIP sensors. His work spawned the first commercial application of MIP sensors.
Allergy Amulet is positioned to become the second company to commercialize MIP sensors, and the first to create MIP sensors for detecting allergenic ingredients. Our sensors combine MIPs with an electrical response to create sensors for detecting molecular tracers of allergenic ingredients in food.
As with any novel application of an existing technology, it is important to recognize and pay tribute to the work of those before us. Learning and studying from the successes and failures of our predecessors is how we will advance as a scientific community, and advance as a society.
- Nazir and the Allergy Amulet Team