The Establishment of Flow Injection Analysis Method for Saliva α-Amylase and Its Application in the Psychological Stress

This study established a novel non-invasive and efficient analysis method which can be applied in research of individual’s psychological stress. Because in the different state of psychological stress, the oral secretion of salivary α-amylase will be changed under the control of the hypothalamuspituitary-adrenal medulla secretion system. Many studies have confirmed that salivary α-amylase measurements may be employed as a non-invasive measure of autonomic (sympathetic) nervous system activation and are related to a variety of behavioral, social, health, and cognitive phenomena in human subjects. In this experiment, a flow injection system for sample analysis and data collection was established to determine the activation of salivary α-amylase. Because flow injection system has the merits of rapid analysis, high precision and accuracy, easily operating and popularizing, it could meet the requirements of quickly and accurately determining of salivary α-amylase. This study collected salivary samples of individual at different times of a day, and drew an individual’s salivary α-amylase secretion curve according to the measured results (one hour for the sampling interval). In addition, after sampling analysis of volunteer’s samples before and after the examination, it was verified that individual’s salivary αamylase secretion would be changed under psychological stress, which suggested that salivary α-amylase could be used as a biochemical marker of individual’s psychological stress changes. The founded method in this paper is easy to be universalized because of its non-invasive and quick features. Key wordsFlow Injection; Salivary α-Amylase; Stress