CoSolvenzeinsatz

CoSolvenzeinsatz refers to the intentional use of a co-solvent, i.e., an additional solvent added to a primary solvent, to improve the solubility of a solute or to modify processing properties. This approach is common in chemistry, pharmaceuticals, polymer science and materials processing, where it can enable dissolution, homogenization, crystallization control, or easier handling of substances that are poorly soluble in a single solvent.

The effect arises from changes in solvent properties such as polarity, dielectric constant, and solubility parameters when a second solvent is introduced. Co-solvents can alter solute–solvent interactions, promote favorable hydrogen bonding or dispersion forces, and create ternary solvent systems with superior solubility characteristics compared with the single solvents. Typical co-solvents include water in combination with ethanol, propylene glycol, or acetone, as well as organic solvents like DMSO, DMF, or acetonitrile, depending on the target solubility and regulatory constraints. In some applications, co-solvents also modify viscosity, boiling point, or phase behavior to aid processing.

Applications encompass pharmaceutical formulation (to dissolve poorly soluble drugs for solutions or injections), crystallization and polymorph control, polymer processing and coating, extraction and purification, and nanomaterial synthesis. Selection of a co-solvent involves assessing solubility data, solvent compatibility, toxicity and regulatory status, residual-solvent limits, and process conditions. Limitations include potential phase separation, incomplete solubility, added cost, and regulatory considerations related to solvent residues.