Chemistry Article Essay

Every day a new breakthrough in science is made, whether it be something little or something big. Scientists all around the world work to solve the unknown and further educate themselves. Some experiments can take years to complete, and some can take just weeks or even days. Either way, discoveries are being made. Many different steps and methods are used just to solve one thing, like in The Poisoned Needle by Fred Senese. This article tells about an unknown illness passing through two different species, towns, and time periods and how the mystery of what it was was discovered by scientists.

Capitola, California was attacked by a bird known as sooty shearwaters in the summer of 1961. These birds were usually nonaggressive, but that morning they were running into glass windows, diving into streetlamps, and even attacking people. A good twenty-six years later, in 1987, another place was struck by this unknown toxin. But that time it was not in birds, it was in people. Blue mussels served in restaurants around Prince Edward Island caused people to vomit, cramps, headaches, and memory loss in some. Being the second outbreak of this toxin and it being so severe, a team of marine biologists and chemists were brought together to solve the mysterious toxin then known as "amnesic shellfish poisoning." They came up with a strategy known as the "divide and discard process" to isolate the toxin. The team started by dividing the mussel samples and injecting different samples into mice. The reaction of the mice would tell whether the toxin was present or not. If the toxin was found in the sample, then another separation technique would be applied. If no toxin was found, the sample would be discarded.

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The next step was solvent extraction. This was so that the mussel samples would not go bad due to heat or harsh solvents. They were extracted with a mild solvent, and then concentrated by evaporation. The team found that the vapor was not toxic, but the residue after was. Other extractions were done to see how the residue separated when added with other mixtures of nonpolar solvents. In the toxic mussels, the visible light absorption spectrum revealed a pattern that was characteristic of phytoplankton pigments. With further investigation, the pigments were found not to be poisonous though, and the aqueous layer consisted of the toxin. Column chromatography was used to separate the layer into organic acids and bases. Acids that were ionized quickly passed through because the resin called XAD-2 would not hold them in their polar ionized form. Out of all the acids that passed through, only one was found to be toxic. By using high performance liquid chromatography, a polar and nonpolar stationary phase that contained the toxin was mixed, and this isolated the toxin by itself. To ensure that that was the isolated toxin, they further broke it down to find its charge, size, and molecular shape.