Chemical Engineering & Technology, Vol.24, No.3, 293-296, 2001
Evaluation of a new high-pressure dispersion unit (HPN) for emulsification
Emulsification plays an important role in the formulation of lipophilic pharmaceutical agents. These substances are often included in the disperse phase of an oil-in-water emulsion. To reach a high bioavailability and a good long-term stability, drop sizes much less than 1 micron are required. For the generation of such emulsions, energy densities of a quality which can only be reached in high-pressure systems, are necessary. Actually available apparatus, such as high-pressure homogenizers fitted with valves, microfluidizer or jet disperser, reach particle sizes of about 0.2 micron in continuous processes. It is indispensable to produce emulsions with smaller globules in order to receive a maximum of diversity in application. Therefore, dispersion units with a higher efficiency in drop breakup are needed. Especially in the case of parenterally administered medicament formulations an average particle size between 0.04 and 0.1 microns is requested which is up to now not reachable by continuous emulsification, In this study the drop breakup behavior of a new high-pressure nozzle is investigated with the example of oil-in-water emulsions and compared to the breakup behavior of a state-of-the-art nozzle and to available data published.