Drug–Polymer Co-Crystals of Dapsone and Polyethylene Glycol: An Emerging Subset in Pharmaceutical Co-Crystals

The role of a polymer as coformer is not a well-explored area for pharmaceutical co-crystals. To investigate this class of materials, a series of seven co-crystals, which are composed of dapsone and polyethylene glycol are reported. A promising strategy for fine-tuning physicochemical properties namely, crystallinity, thermal stability, hygroscopicity, and solubility was discussed via an in-depth structural understanding. Molecular insights into drug–polymer interactions and co-crystal formation are elaborated from the single crystal X-ray structure determination, Fourier transform infrared spectroscopy, differential scanning calorimetry, and hot-stage microscopy studies.