Srivatsa Aithal

Mechanisms of enhanced detection of bacteria with GaAs-based quantum semiconductor microstructures

Biosensing involves using bio-recognition molecules to react and recognize the interrogating molecule and, consequently, transduce this event using photonic or electronic effects. Our group has demonstrated detection of Escherichia coli (E. coli) bacteria down to 10^4 CFU/mL using specially designed quantum semiconductor microstructures [1]. The approach is based on monitoring the photoluminescence effect of quantum well (QW) microstructures, such as GaAs/AlGaAs, covered with a bio-functionalized layer of GaAs. The process of biofunctionalization involves deposition of alkanethiol self-assembled monolayers on GaAs that serves to both stabilize photonic properties of QW microstructures, and to facilitate the attachment of bacteria or virus trapping antibodies.

In the frame of this project, I will investigate the factors influencing stability of the functionalized GaAs surface and the conditions leading to the efficient trapping of targeted molecules. To improve both qualitative and quantitative understanding of the photonic response of semiconductor microstructures, I’ll employ a microfluidic system designed for in situ photonic analysis of surface effects induced by biochemical reactions. A model of phenomena induced with both biofunctionalized microbeads and “user-friendly” E. coli K-12 will be developed with the goal to design a series of enhanced accuracy photonic biosensing protocols. These experiments, in addition to studying kinetics of bacteria binding, will involve an orthogonal biosensing approach, which combines multiple methods of interrogation. A prototypical example of such an approach is an in situ fluorescence analysis of samples with bacteria that follows a PL-based detection step. The practical goal of this research is to develop a highly sensitive and accurate biosensor for remote detection of Legionella pneumophila in water. This bacteria, occurs in natural sources of water and, especially, in water cooling towers, and it could spread through aerosol particles and infect people who breathe in the tower produced mist [2].

[1] V. Duplan, E. Frost, J.J. Dubowski, “A photoluminescence-based quantum semiconductor biosensor for rapid in situ detection of Escherichia coli”, Sensors and Actuators B 160(1), 46-51 (2011).

  • 2012 –
    PhD Electrical Engineering, Biophotonics
    Université de Sherbrooke, Canada
  • 2007 – 2009

    Master of Science in Engineering, Solid State Electronics

    Arizona State University, USA

  • 2001 – 2005
    Bachelor of Engineering in Telecommunication
    Visvesvaraya Technological University, India
Work Experience
  • Nov 2011 – May 2012
    Project Assistant
    Indian Institute of Technology, Bombay, India
  • Jan 2010 – Oct 2011
    Assistant Research Fellow
    Abnova Corporation, Taipei, Taiwan
  • Jun 2009 – Dec 2009
    Assistant Research Technologist
    Arizona State University, USA
  • Oct 2005 – Jun 2007
    Project Engineer
    Wipro Technologies, Bangalore, India
  • Vinay J Nagaraj, Srivatsa Aithal, Seron Eaton, Manish Bothara, Peter Wiktor, Shalini Prasad, NanoMonitor: a miniature electronic biosensor for glycan biomarker detection, Future Medicine, April 2010, Vol. 5, No. 3, Pages 369-378.
Poster Presentations
  • Srivatsa Aithal, Bothara Manish, Gaurav Chatterjee, Lilian Gong, Wellesley College, Sutapa Barua, Amrita Mallik, Kaushal Rege and Shalini Prasad, Endotoxin Detection Using Electrochemical Method and The Effect Nanoscale Confinement, Lab Automation, 2010, Palm Springs, USA

Srivatsa Aithal
Université de Sherbrooke
Interdisciplinary Institute for Technological Innovation (3IT)
3000, boul. de l’Université
Pavillon P2, Office: 4000.10
Sherbrooke, Québec


Phone: +1-819-821-8000 ext. 65724
Fax: +1-819-821-7937