nm dn a marked increase in the saturation solubility occurred by shaking experiments a saturation concentration for the rmkp 22 micro particle suspension of csm 1 98 mg l was determined and for the rmkp 22 nanosuspension a significantly higher csn of 3 29 mg l was determined example 7 an increase in the saturation solubility by reducing the particle size was indeed expected but not at this level an increase in the saturation solubility when the particle size is decreased is postulated in the ostwald freundlich equation voigt r lehrbuch der pharmazeutischen technologie textbook of pharmaceutical technology verlag chemie berlin 1984 but this does not have an effect on particles in the micrometer range saturation solubility as a substance specific parameter dependent solely on temperature equ1 r universal gas constant t absolute temperature m molecular weight the increase in the saturation solubility which occurred to this level is hard to explain with the relatively low difference in particle size the only possible variable parameter in the above equation is the surface tension y according to ostwald freundlich the increase in saturation solubility observed can be explained only by an unexpected change in the surface tension y which must take place due to the homogenization process the energy introduced during the homogenization process must have led to an increase in y and an associated increase in the saturation solubility it is thus evidently possible by conversion of the microparticles into nanoparticles by means of a high energy process to increase the surface tension to such an extent that as a result the saturation solubility increases greatly.