Next Article in Journal
Previous Article in Journal
Sensors 2012, 12(10), 13402-13416; doi:10.3390/s121013402
Article

Theoretical Analysis of the Performance of Glucose Sensors with Layer-by-Layer Assembled Outer Membranes

Jr. 1,* , 2,3
, 3,4
 and 1,*
Received: 22 August 2012; in revised form: 25 September 2012 / Accepted: 28 September 2012 / Published: 1 October 2012
(This article belongs to the Section Biosensors)
View Full-Text   |   Download PDF [727 KB, uploaded 21 June 2014]   |   Browse Figures
Abstract: The performance of implantable electrochemical glucose sensors is highly dependent on the flux-limiting (glucose, H2O2, O2) properties of their outer membranes. A careful understanding of the diffusion profiles of the participating species throughout the sensor architecture (enzyme and membrane layer) plays a crucial role in designing a robust sensor for both in vitro and in vivo operation. This paper reports the results from the mathematical modeling of Clark’s first generation amperometric glucose sensor coated with layer-by-layer assembled outer membranes in order to obtain and compare the diffusion profiles of various participating species and their effect on sensor performance. Devices coated with highly glucose permeable (HAs/Fe3+) membranes were compared with devices coated with PSS/PDDA membranes, which have an order of magnitude lower permeability. The simulation showed that the low glucose permeable membrane (PSS/PDDA) sensors exhibited a 27% higher amperometric response than the high glucose permeable (HAs/Fe3+) sensors. Upon closer inspection of H2O2 diffusion profiles, this non-typical higher response from PSS/PDDA is not due to either a larger glucose flux or comparatively larger O2 concentrations within the sensor geometry, but rather is attributed to a 48% higher H2O2 concentration in the glucose oxidase enzyme layer of PSS/PDDA coated sensors as compared to HAs/Fe3+ coated ones. These simulated results corroborate our experimental findings reported previously. The high concentration of H2O2 in the PSS/PDDA coated sensors is due to the low permeability of H2O2 through the PSS/PDDA membrane, which also led to an undesired increase in sensor response time. Additionally, it was found that this phenomenon occurs for all enzyme thicknesses investigated (15, 20 and 25 nm), signifying the need for a holistic approach in designing outer membranes for amperometric biosensors.
Keywords: amperometric glucose sensors; mathematical modeling; biosensors; Michaelis-Menten constant; enzyme kinetics; layer-by-layer assembly; polymer chemistry; finite difference schemes; differential equations; analyte diffusion amperometric glucose sensors; mathematical modeling; biosensors; Michaelis-Menten constant; enzyme kinetics; layer-by-layer assembly; polymer chemistry; finite difference schemes; differential equations; analyte diffusion
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Croce, R.A., Jr.; Vaddiraju, S.; Papadimitrakopoulos, F.; Jain, F.C. Theoretical Analysis of the Performance of Glucose Sensors with Layer-by-Layer Assembled Outer Membranes. Sensors 2012, 12, 13402-13416.

AMA Style

Croce RA, Jr, Vaddiraju S, Papadimitrakopoulos F, Jain FC. Theoretical Analysis of the Performance of Glucose Sensors with Layer-by-Layer Assembled Outer Membranes. Sensors. 2012; 12(10):13402-13416.

Chicago/Turabian Style

Croce, Robert A., Jr.; Vaddiraju, Santhisagar; Papadimitrakopoulos, Fotios; Jain, Faquir C. 2012. "Theoretical Analysis of the Performance of Glucose Sensors with Layer-by-Layer Assembled Outer Membranes." Sensors 12, no. 10: 13402-13416.



Sensors EISSN 1424-8220 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert