Interdigitated electrodes based on impedance biosensor for sensing peptide LL-37

Annu Int Conf IEEE Eng Med Biol Soc. 2011:2011:71-4. doi: 10.1109/IEMBS.2011.6089899.

Abstract

An antimicrobial peptide, LL-37, is found in an innate defense system of humans. Patients who suffer urinary tract infection (UTI) will generate LL-37 and which is released into urine. LL-37 can be used as an indicator for the diagnosis of UTI. We have designed a biosensor with an interdigitated electrode on a printed-circuit board (PCB). The surface of the electrode was modified with 3-mercaptopropionic acid and immobilized with anti-LL37 antibody to improve the specificity of the biosensor. By de-embedding jig impedance, the impedance associated with the change of LL-37 concentration was calculated. The sensitivity of this biosensor for LL-37 in a urine sample can reach 50 μg/mL.

MeSH terms

  • Antimicrobial Cationic Peptides / urine*
  • Biosensing Techniques / instrumentation*
  • Cathelicidins
  • Conductometry / instrumentation*
  • Electric Impedance
  • Electrodes*
  • Equipment Design
  • Equipment Failure Analysis
  • Humans
  • Immunoassay / instrumentation*
  • Reproducibility of Results
  • Sensitivity and Specificity

Substances

  • Antimicrobial Cationic Peptides
  • Cathelicidins