RESEARCH ON INFLUENCING FACTORS OF SURFACE PLASMON RESONANCE GLUCOSE DETECTION BASED ON D-GALACTOSE/D-GLUCOSE PROTEIN IMMOBILIZED BY AMINE COUPLING METHOD

摘要

Prediction of blood glucose based on measuring the glucose concentration in interstitial fluid is an effectively way to control diabetes. A surface plasmon resonance (SPR) system based on a miniature integrated SPR sensor is set up in this paper to measure the glucose concentration in interstitial fluid, and the D-galactose/D-glucose Binding Protein (GGBP) which can specifically absorb glucose is immobilized onto the SPR sensor surface by amine coupling method for higher sensitivity. The experiment result is affected by various factors, such as the grime on sensor surface, baseline, flow velocity, mass transfer effect, temperature, protein activity, bubbles. Fn this paper these factors are studied systemically byexperiments and some solutions are proposed accordingly: (1) Make sure the sensor surface is clean before it is used. (2) Dynamic baseline can provide the best baseline location during the measurement. (3) Flow velocity of 10uL/min-30uL/min is supposed to be chosen. (4) The density of protein immobilized on the sensor surface should maintain lower to avoid the mass transfer effect. (5) Higher response is got when the temperature is between 26 °C and 30 °C and it is important to keep temperature constant during the experiment. (6) The protein should be preserved with a proper way and make sure it is active during the measurement. (7) The sample should be degassed and filtered before the experiment and make sure there is no air in the pipeline. Through optimizingthe experiment conditions, the sensitivity and stability of the measurement are improved.