You should have chosen the butanol-methyl ethyl ketone-water-ammonia mixture. While none of the solvent systems completely separated all of the dyes, this mixture did the best.
Since Red 40, Blue 1 and Yellow 6 are common dyes, TLC's of mixtures of these dyes were performed to see if they could be separated.
The results showed that only the mixture of Blue 1 and Yellow 6 did not show some separation. Hopefully, the color of the resulting spot (green instead of orange or blue) will be sufficient to determine that both dyes are present.
