Interdigitated electrodes based on impedance biosensor for sensing peptide LL-37.
Lee. Jia-Yi JY; Wang. Chung-Yih CY; Huang. Chi-Fang CF; Cheng. An-Ting AT
Key Findings
- LL‑37 appears in urine during UTIs and can serve as a biomarker for infection.
- An interdigitated electrode on a printed‑circuit board was functionalized with an anti‑LL‑37 antibody.
- The impedance‑based sensor can detect LL‑37 at concentrations as low as 50 µg/mL.
Practical Outcomes
- For most biohackers, this study doesn’t change daily health routines, but it shows a path toward low‑cost, at‑home urine tests for infection markers. Until the sensor is commercialized and validated in real‑world settings, it’s more of a technical proof‑of‑concept than an actionable tool.
Summary
Scientists made a cheap electronic sensor that can spot the immune peptide LL‑37 in urine, which rises when you have a urinary tract infection. The device uses special electrodes and an antibody to detect LL‑37 down to about 50 µg per milliliter.
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.
Study Information
pubmed
2011
10.1109/iembs.2011.6089899