A new hydrate form of diflunisal precipitated from a microemulsion system

作者：Sung Hsuan Lei; Fan Yueh Lin; Yeh Kimberly; Chen Yen Fu; Chen Li Jen^*

来源：Colloids and Surfaces B: Biointerfaces , 2013, 109: 68-73.

DOI：10.1016/j.colsurfb.2013.03.043

• Microemulsion
• Hydrate
• Diflunisal
• Polymorphism
• Dissolution rate

Three microemulsion systems were applied as solvents for polymorph screening of seven active pharmaceutical ingredients (APIs): carbamazepine, piroxicam, sulfaguanidine, nitrofurantoin, theophylline, quercetin, and diflunisal. All the recrystallized compounds were examined by using powder X-ray diffractometry, differential scanning calorimetry, elemental analysis, Karl Fischer titration and dissolution rate. A new crystal form of diflunisal hydrate was discovered by the cooling method of recrystallization in a water-in-oil microemulsion system, composed of water, alkane and dioctyl sodium sulfosuccinate. The new hydrate form of diflunisal was characterized and confirmed to be a stoichiometry of diflunisal:water of 1:1. The other two microemulsion systems were able to convert the anhydrous diflunisal Form I to Form III. The dissolution rate of diflunisal hydrate is unexpectedly much higher than that of anhydrous ones (Forms I and III). All the other six APIs (carbamazepine, piroxicam, sulfaguanidine, nitrofurantoin, theophylline and quercetin) recrystallized from the microemulsion systems were all converted into hydrate form.

• 出版日期2013-9-1