ABSTRACT
Objective To study the color of Ruyi Jinhuang Powder (RJP) placebo by using computer color matching technology and achieve fast preparation of RJP placebo. This work provided a new method to simulate the color of Chinese medicine compound placebo. Methods Using the RJP placebo as an example, computer color matching technology was used to establish a mathematical model to correlate the placebo color parameter L, a*, b* value and the colorant concentration. For a measured medicine compound color, the placebo colorant concentration can then be calculated from the model through data fitting and Newton iterative method. The model accuracy was validated using the color comprehensive evaluation index (ΔE). Results The color parameter L, a*, b* of RJP placebo was 68.302 5, 4.079 5, and 34.484 0. The mass fraction of lemon yellow, amaranth, and blue was 0.837 3%, 0.045 8%, and 0.008 5%. The ΔE value between RJP and its placebo was 2.750 0 ± 0.353 6, and there was no obvious visual difference between the medicine compound and its placebo. Conclusion Computer color matching technology can be used to simulate the color of RJP placebo, and can be widely used in the preparation of Chinese medicine placebo.