ISOELECTRIC-FOCUSING AND CAPILLARY ZONE ELECTROPHORETIC STUDIES USINGLUTEINIZING-HORMONE-RELEASING HORMONE AND ITS ANALOG

Iontophoresis is the movement of charged compounds into and through th e skin under an external electromotive force. A molecule's charge and size, as well as other factors, will determine its ability to be ionto phoresed. One can gain insight into certain electrical aspects of a mo lecule by determining its isoelectric point as well as its electrophor etic mobility. In the present study, isoelectric focusing and capillar y zone electrophoretic studies of luteinizing hormone releasing hormon e, (LHRH) and one of its analogs are performed in order to predict the ir ability to be iontophoresed. The pi of LHRH is determined to be 9.6 while that of its free acid is 6.9. In addition, it is concluded that although the two compounds are chemically similar, the native compoun d is more mobile at pH > 2.5. These results suggest that the native co mpound might be better suited for iontophoretic delivery than is the f ree-acid analog.