Biosensors

• what is a major use of immobilised enzymes?

  is in biosensors
• what do biosensors do?

  • they turn a chemical signal into an electrical signal
  • they rapidly and accurately detect, identify and measure even very low concentrations of important molecules
• what principle do biosensors work on?

  they work on the principle that enzymes are specific and are able to select one type of molecule from a mixture, even at very low concentrations
• what is one particular use of biosensors in blood?

  • detection of blood glucose
  • the enzyme glucose oxidase, immobilised on a selectively permeable membrane placed in a blood sample, binds glucose
  • this produces a small electric current, detected by the electrode and read on a screen
• whats another way enzymes can be immobilised?

  • on test strips, where different strips may detect a variety of molecules
  • testing strips with glucose oxidase immobilised onto them are used for detecting glucose in urine