While lipophilic systems, solid dispersions, particle size reduction and pH control are the principal techniques used to overcome solubility difficulties, we have a wide range of other approaches, such as the ones below, which we use where they will offer results that more closely meet the needs of our clients.

• Co-solvents are based on the principles of cohesive energy density. Where a drug shows poor solubility in water, its solubility can often be increased by the addition of a water-miscible solvent in which the drug has good solubility.
• Complexation uses agents such as cyclodextrins and their derivatives to form intermolecular complexes. These increase the water solubility, dissolution rate and bioavailability of lipophilic drugs for oral or parenteral delivery.
• Micellar solubilisation uses solubilising agents capable of forming micellar structures. When the concentration of surfactants exceeds the Critical Micelle Concentration (CMC), the micelles that are then formed trap the drug within their structures in a process known as micellisation.
• The addition of an electrolyte that does not possess the same ions can raise the solubility of an electrolyte that has limited solubility.