Photoacoustic Determination of Glucose Concentrations in Solutions

• Main Authors: Lin, Tzu-Tsen, 林姿岑
• Other Authors: Yin, Ching-Chung
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/92667953640944522364

碩士 === 國立交通大學 === 機械工程系所 === 104 === Diabetes mellitus is a common endocrine disorder. Continuous monitoring blood sugar is of importance to keep diabetes under control, although currently piercing finger invasively is the most usual method of blood-glucose testing. Noninvasive glucose monitoring will not only avoid physical pain during glucose testing, but also improve life quality of a diabetic. This thesis characterizes glucose concentration in solutions using photoacoustic effect. In experiment, a photoacoustic signal is induced and detected by an ultrasonic transducer when the glucose solution is irradiated by a pulsed Nd:YAG laser. Two experimental setups have been carried out to establish the correlations between amplitude and phase of photoacoustic signals and glucose concentration in solutions. In the first one, photoacoustic signals are induced near the solid-liquid interface between glucose solution and the container. Photoacoustic signal induced in solid media is stable. The difference between the phase at the central frequency of ultrasonic transducers and that at the characteristic frequency of photoacoustic signal has a high correlation, which has been verified by regression and statistical analysis. In the second experiment, the photoacoustic effect is induced in solution by a point-focusing pulsed laser and captured by an immersion ultrasonic transducer. The photoacoustic signal was sensitive to other influences besides glucose concentration. The last experiment results in a difficulty to establish a reliable correlation. Various experimental conditions and their influences have been also studied, such as ultrasonic transducers of different central frequencies, light with distinct wavelengths, and solutions filled with intralipid to emulate scattering properties in human bodies.