Sodium dodecyl sulfate(SDS)/dodecyl triethyl ammonium bromide(DEAB)mixed micelles can transform to vesicles only when the temperature was higher than a critical value.In this study,by using UV-vis spectrometer and fluorescence microscopy,we found that oligo(rU)15 can decrease the critical temperature to a much lower value and hence,induce vesicle formation.Considering the importance of RNAi in gene therapy and the biohazards of viral vector,this finding should provide some helpful information for the transfer of RNA using nonviral vector in gene therapy.