OBJECTIVE:To study the characters, pH value, qualitative identification and concentration determination etc of Sinomine gel in order to establish its quality standard.METHODS:First order derivative spectrum was used as the concentration determination method. RESULTS:The determining wavelength was (272±1) nm.It was found that Sinomine was linear over the range of 25.125 ~ 50.25 μg·ml -1 , and the regression equation was D= 3.67 ×10 -4 + 3.38 ×10 -4 C, r= 0.999 7 ,in that th...