Micro And Nanosensors Flashcards
What is a biosensor
Measure chemical information (metabolites, cytokines…)
Can convert this information into electrical signals
How are different signals generated and transduced?
Electrical:
Electrons ➡️ redox➡️ measurement eg. Diabetic glucose sensor
Ions➡️ activity and conductivity
Optical:
Photons➡️ fluorescence, scattering
Mechanical:
Mass change➡️ mechanical measurement of electrical changes
How can biosensors be used to detect antibodies
Nano cantilevers Ligands immobilised on nano levers Antibiotic binds and distorts lever There is a deflection Produces signal
How do nanowires work
When there is binding to wire
Change in current and voltage of nanowire
How have nano sensors been used in next generation sequencing
Amplify DNA
Beads will carry copy of single sequence
Beads added to microplate wells
Record the pH change in each well when 4dNTPs added sequentially
When base incorporated get voltage change
What is single molecule DNA sequencing
DNA polymerase immobilised on waveguide
Fluorescence from each base will be detected
Whats another example of DNA sequencing using nano sensors
Nanopore
Other examples of nanobiosensors
Quantum dots - fluorescent biosensor
PEBBLES - fluoresce when glucose is present. Measure glucose levels