A new glucose sensor could help people with diabetes gain better control over their blood sugar while eliminating the hassles of daily pinprick tests. The researchers at Pennsylvania State University in State College who developed the sensor were inspired by the magnetic antitheft strips frequently found on commercial merchandise, such as CDs.
The sensor consists of a 4-centimeter-long strip of the magnetoelastic alloy used in antitheft markers. In a magnetic field, the alloy vibrates at a specific frequency. To adapt the material for glucose sensing, the researchers first coated the magnetic strip with a thin polymer layer and then applied a layer of the enzyme called glucose oxidase.
In a solution containing glucose, the enzyme converts that sugar to gluconic acid, increasing the acidity of the polymer. As a result, the polymer expels water, reducing its mass. This alters the frequency at which the strip vibrates in a magnetic field. The higher the concentration of gl