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Updated: Aug 10, 2026

Production, Crystallization and Structure Determination of C. difficile PPEP-1 via Microseeding and Zinc-SAD
Published on: December 30, 2016
Crystal form of cephradine
Young Taek Sohn1, Sun Hee Park
1College of Pharmacy, Duksung Women's University, Seoul 132-714, Korea. ytsohn@duksung.ac.kr
Abstract:
Four crystal forms of cephradine were isolated by recrystallization and characterized by powder X-ray diffractometry, differential scanning calorimetry, and thermogravimetric analysis. The dissolution patterns of four crystal forms of cephradine were studied in water at 37 +/- 0.5 degrees C, 90 rpm for 120 min. The amount dissolved at 120 min was highest for Form I (100%), followed by Form 3 (98.9%), Form 4 (77.83%), and Form 2 (75.55%). After storage for two months at 0% RH (silica gel, 20 degrees C), 52% RH (saturated solution of Na2Cr2O7 x 2H2O/ 20 degrees C), and 95% RH (saturated solution of Na2HPO4/20 degrees C), none of the crystal forms showed transformation.
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