title: Towards toxicity detection using a lab-on-chip based on the integration of MOEMS and whole-cell sensors.
abstract: A lab-on-chip consisting of a unique integration of whole-cell sensors, a MOEMS (Micro-Opto-Electro-Mechanical-System) modulator, and solid-state photo-detectors was implemented for the first time. Whole-cell sensors were genetically engineered to express a bioluminescent reporter (lux) as a function of the lac promoter. The MOEMS modulator was designed to overcome the inherent low frequency noise of solid-state photo-detectors by means of a previously reported modulation technique, named IHOS (Integrated Heterodyne Optical System). The bio-reporter signals were modulated prior to photo-detection, increasing the SNR of solid-state photo-detectors at least by three orders of magnitude. Experiments were performed using isopropyl-beta-d-thiogalactopyranoside (IPTG) as a preliminary step towards testing environmental toxicity. The inducer was used to trigger the expression response of the whole-cell sensors testing the sensitivity of the lab-on-chip. Low intensity bio-reporter optical signals were measured after the whole-cell sensors were exposed to IPTG concentrations of 0.1, 0.05, and 0.02mM. The experimental results reveal the potential of this technology for future implementation as an inexpensive massive method for rapid environmental toxicity detection.
authors: Department of Electrical Engineering-Physical Electronics, Tel-Aviv University, Ramat-Aviv 69978, Israel. noel_elman@hotmail.com
authors: Noel M
authors: NM
authors: Elman
authors: Hadar
authors: H
authors: Ben-Yoav
authors: Marek
authors: M
authors: Sternheim
authors: Rachel
authors: R
authors: Rosen
authors: Slava
authors: S
authors: Krylov
authors: Yosi
authors: Y
authors: Shacham-Diamand
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D002468:Cell Physiological Phenomena / Q000187:drug effects*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005434:Flow Cytometry / Q000295:instrumentation* / Q000379:methods; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D018511:Systems Integration; D018675:Toxicity Tests / Q000295:instrumentation* / Q000379:methods; D014159:Transducers