Synthesis of monodisperse nimesulide nanoparticles in microemulsions E170/isopropyl myristate/water/n-butanol (or isopropanol).

Nanoparticles of nimesulide have been synthesized in two systems of microemulsion: E170/isopropyl myristate/water/n-butanol (or isopropanol). Nanoparticles are monodisperse. In the two microemulsions, the size of the nanoparticles is comprised between 45 and 60 A and also seems to be independent of the factor R ([water]/[E170]) and of the concentration of the nimesulide solubilized in chloroform. The constancy of the size suggests that the size is controlled by thermodynamic stabilization of the nanoparticles with the surfactant. The nature of the cosurfactant does not have an obvious influence on the nanoparticle size. The nanoparticles are instantaneously formed and stay stable during a long period of time (several months).