Open AccessGlucose-sensitive Membrane and Infrared Absorption Spectroscopy for Potential Use as an Implantable Glucose Sensor
Author(s) -
Robert J. Robinson,
Stephen D. McDonald
Publication year - 1992
Publication title -
asaio journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.961
H-Index - 66
eISSN - 1538-943X
pISSN - 1058-2916
DOI - 10.1097/00002480-199207000-00076
Subject(s) - infrared spectroscopy , absorption (acoustics) , infrared , membrane , spectroscopy , absorption spectroscopy , chemistry , materials science , optics , biochemistry , physics , organic chemistry , quantum mechanics , composite material
The applicability of using infrared absorption spectroscopy for an implantable glucose sensor was tested by measuring absorbance at 9.66 microns for glucose in aqueous solution at known concentrations. A commercial Fourier transform infrared spectrometer was used with an attenuated total reflection technique (ATR). Absorbance measurements were reproducible and linearity was excellent (coefficient of correlation: 0.996), in spite of pH and temperature changes over values that span the human physiologic ranges (pH 6.8-7.8, temperature, 32-43 degrees C) and 18-34% decreases in incident infrared energy. The minimum detectable concentration of glucose, however, was 31 mmol/L (560 mg/d) and, to use infrared sources and detectors compatible with an implantable device, an absorbance peak between 1 and 3 microns must be used. To solve the detection sensitivity and wavelength problems, the ATR prism was coated with a hydrophobic liquid membrane. The absorbance of water varied at 2.95 microns in inverse linear proportion to glucose concentration between 2-31 mmol/L (35-560 mg/dL, r = -0.992). Estimated incident infrared energy at 2.95 microns (0.2 micron bandwidth) was low enough to theoretically allow the use of a lithium battery small enough for implantation. These findings support the concept of using infrared absorption spectroscopy for an implantable glucose sensor.