Development Of Primary Reference Material Of Xylose Purity

In recent years the international market raised a research and exploitation boom of functional food, this inject a brand-new content into the food industry. Xylose play a vital role in functional foods because of their unique physiological function, has aroused widespread concern in the world.Sugar certified reference materials have one or more uniform and are good to determine the characteristics of value, and evaluate method of measuring equipment calibration. This project based on imperative high levels of physical inspection standard, develop the research for xylose purity of certified reference materials. The main content and result are as follows:1、Study on the purification:Use of the recrystallization technology for purification, with purity for the indicator of the purification degree. Through the single factor experiments to study the solvent, temperature and times of recrystallization. Results showed that the best condition of purification was ultra pure water as the solvent for three purification under room temperature. Under the above conditions, the purity of99.97%reference material was obtained. The final product was met the requirement for the reference material.2、Detection method:The application of high performance anion exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) and high performance liquid chromatography with nano quantity analyte detection (HPLC-NQAD) are used for quality analysis. Both methods have high sensitivity, good repeatability, high accuracy, simple, fast, etc. and they are suitable for the determination of CRM.3、Physical and chemical properties:study to determine the quality of the CRM, including appearance, solubility, optical rotation, hygroscopic data. For the first time using UPLC-NQAD instrument separation verified a and β two epimer in the water solution of the existence, they can be transformed into each other and finally reach equilibrium.4、Structure characterization:Using high resolution mass spectrometry, infrared spectroscopy, thermogravimetric analysis to character structure of the CRM, confirmed the chemical structure of xylose.5、Homogeneity test:Using random sampling, single-factor analysis of variance method to test Homogeneity of the the CRM. The result shows that the CRM has a good uniformity.6、Stability test:The CRM was investigated by accelerated stability, long-term stability, high temperature stability, light stability and high humidity stability. Using the linear model as the empirical model to analyze the obtained data. The result shows that the CRM is stable under temperature of (25±2)℃, relative humidity of (60±10)%about one year. 7、Evaluation of uncertainty:Each component of uncertainty was calculated the variable parameters among the procedures. The combined uncertainty and extended uncertainty and confidence were finally obtained by synthesized the uncertainties of various component variables. The expanded uncertainty was0.050%and the results of determination could be expressed as (99.97±0.050)%.