Chapter

Hydrogels for Biosensors

DOI: 10.1007/978-3-540-75645-3_6

ABSTRACT Hydrogels are valuable materials for use in biosensors. They can be used for immobilization as well as for creating protecting
layers controlling diffusion and enhancing biocompatibility. Highly stable biosensors use hydrogels for entrapment of enzymes
on microelectrodes. The stability of enzymes in hydrogel membranes for biosensors can be enhanced by choosing the right microenvironment
using micro-hydrogels. The thermodynamic stability of the entrapped enzymes in micro-gels can be characterized via differential
scanning calorimetry (nano-DSC). Hydrogel-based biosensors were characterized by nano-DSC showing that hydrogel membranes
are excellent for creating long-term stable enzyme biosensors. Additionally, smart hydrogels can be used as stimuli responsive
materials enabling sensing as well as actuating performance.

KeywordsMulti-analyte biosensor–Microelectrode-array–Enzyme immobilization–Enzyme stability–Differential scanning calorimetry (DSC)–Chip-calorimeter

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