The growing desire for personalized medicine and healthcare is fueling rapid progress in the field of novel wearable health monitoring technology. Portable electronic platforms are becoming lighter and cheaper, yet there is little advancement in the area of power-free sensors. As wearable technology becomes more widely adopted, there is a need for inexpensive yet accurate health monitoring devices, and non-electronic sensors can meet this demand.
Michele has developed a UV-dose monitoring sensor with completely power-free operation in the form of a flexible, transparent polymer-based sticker. The UV light-sensing mechanism is due to a photo-induced change in the macromolecular structure of the active layer in the tai-polymer sticker. Specifically, the UV-induced photo cleavage of an ortho-nitrobenzyl ester integrated into the backbone of poly(methyl acrylate). Upon photo cleavage, formation of new azo chromophores occur in the film, changing the color of the film from transparent to orange, and alerting the user of the sensor that they have been exposed to a potentially harmful dose of UV light. Learn more about this wearable UV monitoring patch in Michele’s recent ACS Sensors paper .
Stimuli-responsive or “smart” materials are materials which have responsive functionality embedded into their structure. When an external stimulus is applied to the material, an internal change in properties results. For example, a glass that changes color (response) when exposed to high temperature (stimulus) is one example of a smart, thermochromic material. Michele’s specific research focuses on incorporating stimuli-responsive functional groups into the primary or secondary structure of polymers to make them light-responsive or force-responsive. To learn more about smart materials and how to incorporate functionality, check out Michele’s ACS webinar on Smart Polymeric Materials.
A polymer is a macromolecular structure which contains many repeat units. There are multiple ways to synthesize polymers, and Michele currently studies radical polymerization methods. Her work using Atom Transfer Radical Polymerization (ATRP) has enabled location-specific placement of functional groups along the polymer backbone. To learn more about the specific polymers that Michele is studying, check out her recent publications.