Proximal bacterial lysis and detection in nanoliter wells using electrochemistry.
Rapid and direct genetic analysis of low numbers of bacteria using chip-based sensors is limited by the slow diffusion of mRNA molecules. Long incubation times are required in dilute solutions in order to collect a sufficient number of molecules at the sensor surface to generate a detectable signal. To overcome this barrier here we present an integrated device that leverages electrochemistry-driven lysis less than 50 μm away from electrochemical nucleic acid sensors to overcome this barrier. Released intracellular mRNA can diffuse the short distance to the sensors within minutes, enabling rapid and sensitive detection. We validate this strategy through direct lysis and detection of E. coli mRNA at concentrations as low as 0.4 CFU/μL in 2 min, a clinically relevant combination of speed and sensitivity for a sample-to-answer molecular analysis approach.
Institute for Biomaterials and Biomedical Engineering, ‡Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, §Department of Electrical and Computer Engineering, Faculty of Applied Science and Engineering, and ⊥Department of Biochemistry, Faculty of Medicine, University of Toronto , Toronto, ON, Canada M5S 3M2.
Justin D
JD
Besant
Jagotamoy
J
Das
Edward H
EH
Sargent
Shana O
SO
Kelley
D015374:Biosensing Techniques / Q000295:instrumentation; D002458:Cell Fractionation / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D004926:Escherichia coli / Q000235:genetics* / Q000302:isolation & purification*; D008839:Microelectrodes; D044085:Microfluidics / Q000295:instrumentation; D012329:RNA, Bacterial / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis* / Q000235:genetics*
D012329:RNA, Bacterial; D012333:RNA, Messenger