Pharmaceutical cocrystal of antibiotic drugs: A comprehensive review

Pharmaceutical cocrystals, which contain at least one active pharmaceutical ingredient (API), are still an attention-grabbing field for researchers. Two or more discrete molecules unite together by non-covalent bonds, e.g., hydrogen, Van der Waals, and π⋯π bonds. Those bonds are strong enough to stack molecules in solid form lattice, and thus possessing the stability of crystal material, concurrently, non-covalent bonds are weak enough to dissociate when dissolving in water. Therefore, cocrystal delivers drug as a 'ready-to-be absorbed' neutral molecule. Besides, it affects many physicochemical properties, e.g., stability, compressibility, etc. The literature is full of publications that discuss pharmaceutical cocrystals screening and evaluation. This review spots the light on all cocrystals that contain antibiotic (AB) drugs which mentioned in the literature to our knowledge. Focusing on their reported properties like solubility, intrinsic dissolution rate (IDR), stability against humidity/light, powder flowability, compressibility and bioactivity and how they get improved compared to parent AB. Although not many publications imply antimicrobial activity studies in their work, a thorough investigation of how AB cocrystal is affecting bacteria is a persisted necessity. Bacterial ability to develop resistance to known ABs is increasing, making them no longer-efficient. Antibacterial resistance should provoke scientists to use cocrystal modification features to overcome it. This review highlights, classifies and compares all studied AB cocrystals. In addition, it urges research labs, which are interested in cocrystallization, to fill the gap of confronting antimicrobial resistance in their future work.