"Greening" the separation of anthocyanins from coleus plants: TLC and Kadetermination

CHED 377

Leslie Revoredo, lrevo001@fiu.edu1, Dionne Dickson, ddick003@fiu.edu2, Mayra Exposito, exposito@fiu.edu3, Andrew Tomonto, atomonto7@yahoo.com4, Andrew Evans, eaevans18@yahoo.com5, Michael Gregory, m.g.r.e.g.o.r.y@hotmail.com4, Christian Oliveros, champian@bellsouth.net4, Daniel Ruizcalderon, dandman1024@yahoo.com4, and Kyle Roque, kroque22@yahoo.com6. (1) Department of Chemistry, Florida International University, Biscayne Bay Campus, Science Club, AC II Room 340, North Miami, FL 33181, (2) Chemistry Department, Florida International University, Biscayne Bay Campus, Science Club, AC II Room 340, North Miami, FL 33181, (3) Department of Chemistry, Florida International University Biscayne Bay Campus, 3000 NE 151 Ave, AC II Room 340, North Miami, FL 33181, (4) Christopher Columbus High School, 3000 SW 87th Ave, Miami, FL 33165, (5) Chistopher Columbus High School, 3000 SW 87th Ave, Miami, FL 33165, (6) Christpher Columbus High School, 3000 SW 87th Ave, Miami, FL 33165
During the Summer 2007 semester, a small number of students from Christopher Columbus High School in Miami received the opportunity to work with college students on a special chemistry project. To demonstrate the effectiveness of an incremental greening process on chemistry curricula, environmentally-friendly laboratory procedures were explored. They worked with two different types of coleus leaves from Coleus Blumei, the coleus “Dark Star” and the “Chelsea Rose”. The goal was to find the most efficient combination of solvents to run the TLC. To reach this goal we designed a 4^3 full factorial experiment. The developing solvent system was made with a combination of 2-propanol, acetone, and water in 64 different proportions. The pigments from the coleus leaves were extracted using acidic methanol, it was centrifuged and the supernatant liquid was separated. Using UV-VIS, IR, SPARTAN and microlab interface we were able to determine the structure and the Ka of anthocyanins (flavylium cation).
 

Undergraduate Research Poster Session: Chemical Education
11:00 AM-1:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Poster

Division of Chemical Education

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008