Experimental Testing of Shape and Polarity Preferences

The above database results can be translated into simple qualitative rules for selecting co-crystal formers. Choosing co-formers with similar shapes, similar fractional polarities and similar dipole moments to the API should increase the chances of successful co-crystal formation. Because of the relative weakness of the underlying trends, a large number of experiments is required to demonstrate convincingly that consideration of these factors improves the success rate of cocrystal screening experiments. 

The toxicity of the co-crystal formers was not considered, since the purpose of the experiments was to confirm the physical significance of the results from the database study. Of course, only non-toxic substances can be used when developing a pharmaceutical co-crystal, but this diiference is expected to have 

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