Objective To establish a method for simulataneous determination of 18 free amino acids in snake venom. Methods Preparation of free amino acid samples by membrane. HPLC analysis was performed after derivatization by using phenyl isothiocyanate (PITC) as a derivative reagent, samples were analyzed on Ultimate LP-C18 column with gradient elution column of 0.05 mol/L sodium acetate buffer and methanol-acetonitrile- water (40:40:20), and current speed was1.0 mL/min, and the column temperature was set at 35℃, and detection wavelength was 254nm. Results The 18 kinds of amino acids showed a good linearity with the correlation coefficients ≥0.99. The recovery rate was 74.59%~110.62%. Snake venom contained 17 kinds of amino acids, the total content of amino acids was 0.2%. Conclusion The method was accurate, reproducible and reliable, and can be used for the determination of amino acids in snake venom and related products.

Objective:To develop the Oral Health Protective Motivation Questionnaire for Adults and test its reliability and validity.Methods:This study is a cross-sectional study. The initial version of Oral Health Protective Motivation Questionnaire for Adults was constructed based on the protection motivation theory, referring to the Oral Health Guideline for Chinese Population, through literature review, semi-structured interviews and expert consultation. From March to April 2022, 610 adults from 6 communities in Qingdao were selected by convenient sampling to conduct a questionnaire survey. The questionnaire was initially evaluated by item analysis and reliability and validity testing. A total of 610 questionnaires were distributed, and 599 valid questionnaires were recovered, with a valid recovery rate of 98.20% (599/610) . Results:The Oral Health Protective Motivation Questionnaire for Adults included 35 items. Exploratory factor analysis extracted six common factors, namely severity, susceptibility, internal and external rewards, response cost, response efficacy, and self-efficacy, the explanatory variation of each factor was 60.28% to 74.23%. Confirmatory factor analysis showed that the six factors model fitted well. Cronbach's α coefficient of the total questionnaire was 0.946, and the Cronbach's α coefficient of each dimension was from 0.744 to 0.937. The half-reliability coefficient of the total questionnaire was 0.853.Conclusions:The Oral Health Protective Motivation Questionnaire for Adults has good reliability and validity, and can be used to evaluate the adult oral health protection motivation.