title: Formation mechanism of a new carbamazepine/malonic acid cocrystal polymorph.
abstract: A new 2/1 carbamazepine (CBZ)/malonic acid (MA) cocrystal polymorph form C was formed using a vibrational rod mill, whereas the known cocrystal polymorph form A was prepared using a ball mill. IR measurements showed that the interaction between CBZ and MA in cocrystal form C was formed by amide-carboxylic acid heterosynthons, similar to that in cocrystal form A. However, NMR results showed that the molecular states of CBZ at the dibenzazepine ring appeared to be different, which could be due to variation in either the conjugation of the aromatic rings or the π-π interaction of CBZ. Factors affecting the formation of cocrystal polymorphs, such as heat and force, were investigated to clarify the formation mechanism.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chiba 260-8675, Japan.
authors.forename: Waree
authors.initials: W
authors.lastname: Limwikrant
authors.forename: Aiko
authors.initials: A
authors.lastname: Nagai
authors.forename: Yumi
authors.initials: Y
authors.lastname: Hagiwara
authors.forename: Kenjirou
authors.initials: K
authors.lastname: Higashi
authors.forename: Keiji
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Kunikazu
authors.initials: K
authors.lastname: Moribe
mesh_terms: D002220:Carbamazepine / Q000737:chemistry*; D003460:Crystallization; D004339:Drug Compounding / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D008314:Malonates / Q000737:chemistry*; D033362:Powder Diffraction; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D008314:Malonates; D002220:Carbamazepine; C030290:malonic acid