Middle Infrared, Quantum Cascade Laser Optoelectronic Absorption System for Monitoring Glucose in Serum

Abstract

Advances in middle infrared technology are leading researchers beyond the Fourier transform infrared spectrometer and to the quantum cascade laser. While most research focuses on gas-phase detection, recent research explores its use for condensed-phase matter studies. This work investigates its use for monitoring biologically relevant samples of glucose in serum. Samples with physiological glucose concentrations were monitored with a laser at 1036 cm-1. A 0.992 R2 linearity value was observed. In addition, using another laser at 1194 cm-1 as a measure of the background spectroscopic characteristics, a linearity of 0.998 R2 was observed. The average predictive standard errors of the mean (SEM) were 32.5 and 24.7 mg/dL, respectively, for each method. Quantum cascade lasers could be used to develop middle infrared devices for uses beyond the confines of the laboratory.

Noninvasive glucose detection in human skin using wavelength modulated differential laser photothermal radiometry

“…In contrast, the mid-infrared (MIR) region involves a prominent glucose absorption band which is peaked at ca. 9.7 μm [27], and is isolated from other interfering peaks in human blood [21,25,26,28–30]. Difficulties in the MIR range are the strong water absorption and the resulting background fluctuation for single-ended and contact methods.…”

Recent Advances in Application of Biosensors in Tissue Engineering

“…The responsiveness of these methods, however, is considerably slow due to the weak glucose absorption bands (combination bands) and the presence of various undesired bands from other constituents of the system. On the other hand, the mid-infrared (MIR) region involves a prominent glucose absorption band and it gives isolated band in human blood [54–57]. However, MIR method is limited by strong water absorption and background fluctuation that frequently hamper the results.…”

HITRAN/HITEMP Spectral Databases and Uncertainty Propagation by Means of Monte Carlo Simulation with Application to Tunable Diode Laser Absorption Diagnostics

“…The broadening parameters are generally quoted at some reference temperature, typically 296 K, and then corrected to the appropriate temperature using the semi-empirical temperature correction given by (Ref. 18) (14) The temperature correction exponent generally has values near 0.75.…”

“…Utilizing the equations governing the absorption process in Eqs. (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19), a spectral transmittance is nonlinear-fitted to the measured spectral transmittance data by iteratively adjusting the absorbing specie number density. Unlike the previous two techniques, this technique does not utilize integration over the spectral line and thus does not possess the indirect dependency on the line width that is inherent with a line integration technique when one cannot scan the entire absorption feature.…”

“…Also, at elevated temperatures the pressure-broadening parameters decrease (Eq. [14]) resulting in loss sensitivity to total number density. The equation used to summarize this method is given by (27) …”