|MadSci Network: Chemistry|
Dear Chantal, Sounds like a great product idea! Unfortunately, you are limited in what ingredients are available... There are only two types of glow in the dark materials: pigments (not soluble) or dyes. There is only one dye I know of that happens to be the chemical inside fireflies: luminol. The problem with this dye is that it relies on other ingredients such as bases and peroxide to work and would be difficult to classify as non-toxic. In the pigment category, zinc sulfide (doped with copper) is the classic material used which only glows for a short period of time after being exposed to light. There are two other types: organic pigments (glow for a very long period of time but are expensive and only available overseas) which cannot come in contact with water in order to glow, and "alkali earth aluminates" that are very similar to the zinc sulfides except they are a little more expensive and glow for longer periods of time. In short, in order to make a non-toxic bubble solution, you must either purchase zinc sulfide (copper doped) or some of the alkali earth aluminates. There are numerous companies you can obtain these from; just search the Internet for "phosphorescent pigments". So, you can either buy or make bubble solution to which you can add the glow pigment. I suggest making the bubble solution which would not be hard: buy glycerine from the nearest drug store, along with lemon Joy dish detergent. Classic bubble solution is made by mixing 1 cup detergent with 16 cups of water and three tablespoons of glycerine. In this case, you may opt to add much more glycerine and less water (to make the water thicker) so that the pigment will stay suspended a little longer than with clasic bubble solution you can buy. Just before blowing the bubbles, you will need to shine light on a clear jar containing your concoction, and then give it a healthy stir to temporarily re-suspend the pigment. As for the different color bubbles, only fluorescent colors will add to the already greenish-yellow glow of the pigment, so you will need to get fluorescent dyes or pigments to add to your concoction. Again, search the Internet for a company who can send you some samples of fluorescent dyes or pigments to try. Good luck!
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