*2.4. Solubility Determination*

The water solubility of each cocrystal was determined in triplicate, and compared with that of the corresponding pyridinecarboxamides coformer. For this, a quantitative method based on the saturation of solutions at room temperature was used as follows: An excess of coformer or cocrystal was dispersed in 0.5 or 1 mL of Milli-Q water in Eppendorf tubes and left stirring for a week at room temperature. The samples were centrifuged at 12,000 rpm for 45 min, in each case the supernatant liquid was removed, and the corresponding solid was dried and weighed. This led us first to determine the solubility for **pic** (S = 177 mg/mL), **nam** (S = 500 mg/mL), **inam** (S = 192 mg/mL) and **DL-H2ma** (S = 159 mg/mL), and then that of their respective cocrystals.
