Screening and characterization of cocrystal formation of metaxalone with short-chain dicarboxylic acids induced by solvent-assisted grinding approach

• Solvent-assisted grinding can easily create a cocrystal formation.
• Metaxalone and n = 2 of short-chain dicarboxylic acids can form cocrystal.
• The cocrystal formation is also easily induced by a unique DSC-FTIR microspectroscopy.

A solvent-assisted grinding approach was used to investigate the possible cocrystal formation between metaxalone and short-chain dicarboxylic acids (HOOC(CH2)nCOOH, n = 0–3). Differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) microspectroscopy, and powder X-ray diffraction (PXRD) were used to verify the cocrystal formation between metaxalone and each dicarboxylic acid. As a standard reference, a cocrystal was prepared by solvent evaporation method. The cocrystal formation was also quickly estimated by using a one-step simultaneous DSC-FTIR microspectroscopy. The present study indicates that only n = 2 of short-chain dicarboxylic acids such as succinic acid, fumaric acid and maleic acid can form a cocrystal with metaxalone through solvent-assisted grinding in a short time. Moreover, this cocrystal formation was easily screened and estimated using a unique DSC-FTIR microspectroscopy.

Solvent-assisted grinding approach can create a cocrystal between metaxalone and succinic acid, fumaric acid or maleic acid. The cocrystal formation was easily screened and identified using a unique DSC-FTIR microspectroscopy.Figure optionsDownload as PowerPoint slide