title: In-situ synchrotron wide-angle X-ray diffraction as a rapid method for cocrystal/salt screening.
abstract: The purpose of this work was to explore in-situ synchrotron wide-angle X-ray diffraction (WAXD) as a rapid and accurate tool to screen and monitor the formation of cocrystal/salts during heating. The active pharmaceutical ingredients (caffeine, carbamazepine and lamotrigine) were respectively mixed with the coformer (saccharin), and then heated by the hot stage. Real-time process monitoring was performed using synchrotron WAXD to assess cocrystal formation and subsequently compared to differential scanning calorimetry (DSC) measurements. The effect of heating rates and cocrystal growth behavior were investigated. Synchrotron WAXD was fast and sensitive to detect cocrystal formation with the appearance of characteristic diffraction rings, even at the heating rate of 30°C/min, while DSC curves showed overlapped peaks. Unlike the indirect characterization of DSC on endo/exothermic peaks, synchrotron WAXD can directly and qualitatively determine cocrystal by diffraction peaks. The diffraction intensity-temperature curves and the corresponding first-derivative curves clearly exhibited the growth behavior of cocrystal upon heating, providing useful information to optimize the process temperature of hot melt extrusion to continuously manufacture cocrystal. The study suggests that in-situ synchrotron WAXD could provide a one-step process to screen cocrystal at high efficiency and reveal the details of cocrystal/salts growth behavior.
authors: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors: Pin
authors: P
authors: Dong
authors: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors: Ling
authors: L
authors: Lin
authors: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors: Yongcheng
authors: Y
authors: Li
authors: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors: Zhengwei
authors: Z
authors: Huang
authors: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China.
authors: Tianqun
authors: T
authors: Lang
authors: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China. Electronic address: chuanbin_wu@126.com.
authors: Chuanbin
authors: C
authors: Wu
authors: School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou 510006, PR China. Electronic address: luming3@mail.sysu.edu.cn.
authors: Ming
authors: M
authors: Lu
mesh_terms: D002110:Caffeine / Q000008:administration & dosage / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning / Q000379:methods; D002220:Carbamazepine / Q000008:administration & dosage / Q000737:chemistry*; D003460:Crystallization; D006358:Hot Temperature; D000077213:Lamotrigine; D012439:Saccharin / Q000737:chemistry; D017356:Synchrotrons; D014227:Triazines / Q000008:administration & dosage / Q000737:chemistry*; D014961:X-Ray Diffraction / Q000379:methods*
chemical_list: D014227:Triazines; D002220:Carbamazepine; D002110:Caffeine; D012439:Saccharin; D000077213:Lamotrigine
keywords: Cocrystal; Hot melt extrusion; Synchrotron radiation; Wide-angle X-ray diffraction