6533b839fe1ef96bd12a6e9d
RESEARCH PRODUCT
Time-monitoring sensor based on oxygen diffusion in an indicator/polymer matrix
Theodor DollThomas HaasJuan-jesús Velasco-vélezPeter MarekGabriele Sadowskisubject
chemistry.chemical_classificationVinyl alcoholChemistryDiffusionMetals and AlloysAnalytical chemistrychemistry.chemical_elementPolymerCondensed Matter PhysicsOxygenRedoxSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsMatrix (chemical analysis)Chemical kineticschemistry.chemical_compoundMaterials ChemistryElectrical and Electronic EngineeringInstrumentationMethylene bluedescription
Abstract A time-monitoring sensor based on the oxidation of leuco methylene blue (LMB) to methylene blue (MB) was developed. The sensor changes its color from yellow to green in the presence of oxygen and was integrated into a poly(vinyl alcohol) matrix. The diffusion of the oxygen in the polymer matrix as well as the oxygen uptake due to the oxidation reaction determines the time monitoring of the sensor. A physical model has been developed that accounts for both the diffusion as well as the oxidation reaction. For this purpose, the reaction kinetics was determined experimentally. Moreover, the diffusion coefficient of oxygen was determined and concentration profiles in the polymer matrix modeled. Based on these modeling, the time sensor could be calibrated very precisely. This widely applicable, low-cost visual sensor is compatible with current technologies for the processing of plastics and can be integrated into different types of packaging, e.g. for application in freshness monitoring of consumer goods.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2013-03-01 | Sensors and Actuators B: Chemical |