An integrated circuit for chip-based analysis of enzyme kinetics and metabolite quantification

Cheah, B. C. , MacDonald, A. I., Martin, C., Streklas, A. J., Campbell, G., Al-Rawhani, M. A., Nemeth, B., Grant, J. P. , Barrett, M. P. and Cumming, D. R.S. (2016) An integrated circuit for chip-based analysis of enzyme kinetics and metabolite quantification. IEEE Transactions on Biomedical Circuits and Systems, 10(3), pp. 721-730. (doi: 10.1109/TBCAS.2015.2487603) (PMID:26742138)

Abstract

We have created a novel chip-based diagnostic tools based upon quantification of metabolites using enzymes specific for their chemical conversion. Using this device we show for the first time that a solid-state circuit can be used to measure enzyme kinetics and calculate the Michaelis-Menten constant. Substrate concentration dependency of enzyme reaction rates is central to this aim. Ion-sensitive field effect transistors (ISFET) are excellent transducers for biosensing applications that are reliant upon enzyme assays, especially since they can be fabricated using mainstream microelectronics technology to ensure low unit cost, mass-manufacture, scaling to make many sensors and straightforward miniaturisation for use in point-of-care devices. Here, we describe an integrated ISFET array comprising 216 sensors. The device was fabricated with a complementary metal oxide semiconductor (CMOS) process. Unlike traditional CMOS ISFET sensors that use the Si3N4 passivation of the foundry for ion detection, the device reported here was processed with a layer of Ta2O5 that increased the detection sensitivity to 45 mV/pH unit at the sensor readout. The drift was reduced to 0.8 mV/hour with a linear pH response between pH 2 – 12. A high-speed instrumentation system capable of acquiring nearly 500 fps was developed to stream out the data. The device was then used to measure glucose concentration through the activity of hexokinase in the range of 0.05 mM – 231 mM, encompassing glucose’s physiological range in blood. Localised and temporal enzyme kinetics of hexokinase was studied in detail. These results present a roadmap towards a viable personal metabolome machine.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Al-Rawhani, Dr Mohammed and Campbell, Mr Gordon and Grant, Dr James and Nemeth, Mr Balazs and Cumming, Professor David and MacDonald, Dr Alasdair and Barrett, Professor Michael and Cheah, Dr Boon Chong and Martin, Mr Christopher
• Authors: Cheah, B. C., MacDonald, A. I., Martin, C., Streklas, A. J., Campbell, G., Al-Rawhani, M. A., Nemeth, B., Grant, J. P., Barrett, M. P., and Cumming, D. R.S.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity; College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: IEEE Transactions on Biomedical Circuits and Systems
• Publisher: IEEE
• ISSN: 1932-4545
• ISSN (Online): 1940-9990
• Published Online: 06 January 2016
• Copyright Holders: Copyright © 2015 IEEE
• First Published: First published in IEEE Transactions on Biomedical Circuits and Systems 10(3): 721-730
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher.

Related URLs

• Research Data

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
60582	1	The Multi-Corder: Poly-Sensor Technology	David Cumming	Engineering & Physical Sciences Research Council (EPSRC)	EP/K021966/1	ENG - ENGINEERING ELECTRONICS & NANO ENG
69042	1	Glasgow Molecular Pathology (GMP) Node	Karin Oien	Medical Research Council (MRC)	MR/N005813/1	ICS - EXPERIMENTAL THERAPEUTICS