On the Use of Nonsteroidal Anti-Inflammatory Drugs as Rheology Modifiers for Surfactant Solutions.

Surfactant molecules can give rise to different morphological structures, depending on numerous parameters such as temperature, surfactant concentration, and salinity. Specifically, the salt content can be easily tuned in a way to induce morphological transitions and modulate the rheological response. It is shown that nonsteroidal anti-inflammatory drugs can be used in the same way as classical binding salts in changing the rheological properties of the resulting gel-like system. On the one hand, the experimental results show that by tuning small details in the molecular conformation of the drug and its concentration in the micellar solution, it is possible to obtain the desired mechanical response. On the other hand, the results prove that rheology can be considered as a powerful tool to detect the drug release content, with obvious consequences on possible applications.