The Artificial Synthesis of Raphide

Abstract

Have you ever had an itchy mouth after eating yam? This is because the calcium oxalate needle shaped crystals, known as raphide, is contained in the plant that irritate the skin. raphide has been studied in various fields such as medicine and agriculture because of their characteristic effects. Although previous studies have reported useful effects, no successful artificial synthesis of raphide crystals has yet been reported. Therefore, I researched for factors that affect the synthesis of raphide. First, I conducted targeted experiments on drop rate, rotation speed, and concentration. As a result, it was found that the drop rate and rotation speed are factors that change the crystal structure. When these crystals were analyzed by X-ray crystallography, it was confirmed that they were calcium oxalate crystals. However, they were not raphide, so I attempted to synthesize them using a catalyst. For the catalyst, I decided to use the cell fluid part of aloe vera and an aqueous solution of amino acids. When the synthesized crystals were observed under a microscope, there were few raphide could be seen. Furthermore, since the extracted crystals may be the catalytic amino acid, ninhydrin reaction was performed on the filtrate and crystals, and no reaction was observed in both. Since it reacted in the solution before the experiment, I can say that it is calcium oxalate crystal. Therefore, it can be said that the synthesis of raphide was successful and the purpose of the research was achieved.