Enzymeless electrochemical sensor for detection of hydrogen peroxide in living cells

Introduction

Hydrogen peroxide (H2O2) is an important biomarker of oxidative stress in human physiology. H2O2 released by live cells can be associated with medical disorders like Alzheimer’s disease, Parkinson’s disease, myocardial infarction, and cancer1, 2. Traditional peroxide sensors predominantly operate on optical and electrochemical techniques and employ peroxidase enzymes (which limits shelf life of sensor) for selective detection of H2O2. Due to the low amount of H2O2 produced by living cells, a highly sensitive detection platform is required. Electrochemical sensors consisting of microelectrode arrays (MEAs) offer the possibility of providing low detection limit of target analytes3, 4. Coupled with suitable peroxidase mimicking entities, like transition metal complexes, the MEA based sensing platform can detect low concentrations of H2O2 with high selectivity in a complex cellular environment. To summarize, the developed sensor will combine the low detection limits offered by MEAs and high selectivity of peroxidase mimicking molecules towards H2O5. The envisioned detection platform has potential application in clinical diagnostics.

Your tasks: 

  1. Modification of MEAs with transitions metal complexes and their composites
  2. Characterize the modified MEAs 
  3. Conducting electrochemical measurements to
    • Generate calibration plot for detection of H2O2
    • Conduct selectivity studies.
    • Detection of H2O2 released by living cell

You will be a part of an interdisciplinary working environment and will have the opportunity of learning the following techniques:

  1. Sensor fabrication
  2. Voltammetry, amperometry, and electrochemical impedance spectroscopy
  3. Enzyme-linked immunosorbent assays
  4. Handling of real samples (cells in this case)

 

Requirements

We are looking for a highly dedicated and motivated candidate to work on an interdisciplinary research topic. The candidate is expected to have:

  1. Excellent analytical and experimental skills
  2. Desired background: Electrical engineering, Chemistry, or Physics
  3. Theoretical knowledge related to electrochemistry and working principles of biosensors 

Possible starting date & further information

As soon as possible. The duration is 6 months (Master’s project or internship). For further details and application, contact Bhawana Thakur.

References

  1.  Wei, Y.; Zhang, Y.; Liu, Z.; Guo, M., A novel profluorescent probe for detecting oxidative stress induced by metal and H2O2 in living cells. Chemical Communications 2010, 46 (25), 4472-4474.
  2. Zhang, T.; Gu, Y.; Li, C.; Yan, X.; Lu, N.; Liu, H.; Zhang, Z.; Zhang, H., Fabrication of Novel Electrochemical Biosensor Based on Graphene Nanohybrid to Detect H2O2 Released from Living Cells with Ultrahigh Performance. ACS Applied Materials & Interfaces 2017, 9 (43), 37991-37999.
  3. Huang, X.-J.; O'Mahony, A. M.; Compton, R. G., Microelectrode Arrays for Electrochemistry: Approaches to Fabrication. 2009, 5 (7), 776-788.
  4.  Wolfrum, B.; Kätelhön, E.; Yakushenko, A.; Krause, K. J.; Adly, N.; Hüske, M.; Rinklin, P., Nanoscale Electrochemical Sensor Arrays: Redox Cycling Amplification in Dual-Electrode Systems. Accounts of Chemical Research 2016, 49 (9), 2031-2040.
  5. Ragg, R.; Tahir, M. N.; Tremel, W., Solids Go Bio: Inorganic Nanoparticles as Enzyme Mimics. 2016 (13‐14), 1906-1915.