Format

Send to

Choose Destination
See comment in PubMed Commons below
J Diabetes Sci Technol. 2012 Nov 1;6(6):1436-44.

Continuous monitoring of glucose in subcutaneous tissue using microfabricated differential affinity sensors.

Author information

1
Department of Mechanical Engineering, Columbia University, New York, NY 10027, USA. xh2123@columbia.edu

Abstract

OBJECTIVE:

We describe miniaturized differential glucose sensors based on affinity binding between glucose and a synthetic polymer. The sensors possess excellent resistance to environmental disturbances and can potentially allow wireless measurements of glucose concentrations within interstitial fluid in subcutaneous tissue for long-term, stable continuous glucose monitoring (CGM).

METHODS:

The sensors are constructed using microelectromechanical systems (MEMS) technology and exploit poly(N-hydroxy-ethyl acrylamide-ran-3-acrylamidophenylboronic acid) (PHEAA-ran-PAAPBA), a glucose-binding polymer with excellent specificity, reversibility, and stability. Two sensing approaches have been investigated, which respectively, use a pair of magnetically actuated diaphragms and perforated electrodes to differentially measure the glucose-binding-induced changes in the viscosity and permittivity of the PHEAA-ran-PAAPBA solution with respect to a reference, glucose-unresponsive polymer solution.

RESULTS:

In vivo characterization of the MEMS affinity sensors were performed by controlling blood glucose concentrations of laboratory mice by exogenous glucose and insulin administration. The sensors experienced an 8-30 min initialization period after implantation and then closely tracked commercial capillary glucose meter readings with time lags ranging from 0-15 min during rapid glucose concentration changes. Clarke error grid plots obtained from sensor calibration suggest that, for the viscometric and dielectric sensors, respectively, approximately 95% (in the hyperglycemic range) and 84% (ranging from hypoglycemic to hyperglycemic glucose concentrations) of measurement points were clinically accurate, while 5% and 16% of the points were clinically acceptable.

CONCLUSIONS:

The miniaturized MEMS sensors explore differential measurements of affinity glucose recognition. In vivo testing demonstrated excellent accuracy and stability, suggesting that the devices hold the potential to enable long-term and reliable CGM in clinical applications.

PMID:
23294791
PMCID:
PMC3570886
DOI:
10.1177/193229681200600625
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Atypon Icon for PubMed Central
    Loading ...
    Support Center