Investigation on crystal structure and moisture sorption properties of riboflavin
- Author:
Jing XIONG
1
Author Information
- Publication Type:Journal Article
- Keywords: Adsorption-desorption isotherm; DVS; IR; Moisture; Polymorphism; Riboflavin; Sorption dynamics; Thermal analysis; XRD
- From: Chinese Pharmaceutical Journal 2015;50(16):1436-1440
- CountryChina
- Language:Chinese
- Abstract: OBJECTIVE: To establish the detection technology of riboflavin polymorphism, and investigate the moisture sorption properties of riboflavin. METHODS: The two crystal forms of riboflavin were characterized by different analysis methods, such as powder X-ray diffraction method (p-XRD), differential scanning calorimetry method (DSC) and infrared spectrum method (IR). Dynamic vapor sorption (DVS) analysis was adopted to acquire moisture sorption dynamics of the two crystal forms. The influences of temperature, humidity and light on crystal transformation were explored. RESULTS: The crystal forms of two batches of riboflavin samples were identified as anhydrate I and monohydrate, respectively. The monohydrate could be obtained by recrystallizing in DM-SO. The monohydrate was hygroscopic, the number of crystal water may change at different relative humidities, and the moisture sorption dynamics of the monohydrate was greatly influenced by temperature. The anhydrate I was almost non-hygroscopic, and temperature hardly affected its moisture sorption dynamics. CONCLUSION: Characteristic data for riboflavin polymorphism are obtained, and the results show that anhydrate I is more stable than monohydrate. This study indicates that DVS could be used in studies on drug polymorphism.
