Study of placebo used in the Chinese medicinal clinical trail / 国际中医中药杂志

ABSTRACT

Objective To study the influencing factors of the colorants used in the placebo of herbal medicine.Methods The effect of pH value,temperature,and illumination and sterilization method on the coloring of the pigments like carmine,sunset yellow 60,brilliant blue 60 and caramel were investigated by determining the Lab value with the instrument.Results PH value of solution had effects on the coloring of carmine and sunset yellow 60,but no effects on the brilliant blue 60 and caramel.When pH values of the solutions were adjusted to 10,chromatic aberration values of carmine and sunset yellow 60 were 17.29 and 27.29,respectively; In the conditions of acidification,the color of carmine and sunset yellow 60 solutions were not changed much; short heating and illumination had no effects on all the four pigments,and all the chromatic aberration values were less than 1.5; 60Co-ray irradiation had great effects on the coloring,and the chromatic aberration values of carmine,sunset yellow 60,brilliant blue 60 and caramel solutions after 60Co-ray irradiation were 12.43,22.45,37.53 and 19.22,respectively; While autoclaving (121 ℃,20 min) would not change the color of solution,and all those chromatic aberration values were less than 1.5.Conclusion These colorants are suitable for the placebo preparation of Chinese medicine decoction,which is recommended to be added in the preparation of the final link.60Co-ray irradiation sterilization is forbidden.