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Separations and purifications

9 videos
5C: Did you know that digitalis, one of the oldest medicines used to increase cardiac contractility, is derived from the foxglove plant? When you are in the Amazon rainforest searching for a cure for cancer in a new exotic plant, your potential miracle drug of interest is not originally pure - it must be separated from the other contaminating components. Through these tutorials you will learn how to separate and purify chemical compounds using organic chemistry lab techniques such as extraction, distillation, chromatography, and gel electrophoresis.

Simple and fractional distillations

VIDEO 9:30 minutes
Learn how chemicals can be separated and purified through distillation, a process which separates them based on their respective boiling points. By Angela Guerrero.

Extractions

VIDEO 8:39 minutes
Learn about how chemicals can be separated through acid-base extraction. By Angela Guerrero.

Basics of chromatography

VIDEO 9:16 minutes
Understand the basic principles of different kinds of chromatography: paper, thin layer, column, size-exchange, ion exchange, affinity, HPLC, and. By Angela Guerrero.

Thin layer chromatography (TLC)

VIDEO 5:07 minutes
Learn about how chemicals can be separated based on polarity through thin layer chromatography (TLC). By Angela Guerrero.

Calculating retention factors for TLC

VIDEO 7:21 minutes
Learn how to calculate retention factors (Rf) for thin layer chromatography (TLC). By Angela Guerrero.

Column chromatography

VIDEO 6:39 minutes
Learn how to separate chemicals using column chromatography. By Angela Guerrero.

Gas chromatography

VIDEO 8:38 minutes
Understand how to separate and purify chemicals through gas chromatography and how to interpret a gas chromatogram. By Angela Guerrero.

Gel electrophoresis

VIDEO 6:59 minutes
Learn how gel electrophoresis separates DNA and protein fragments based on size and why one would use agarose gel electrophoresis versus SDS-PAGE. By Angela Guerrero.

Resolution of enantiomers

VIDEO 5:02 minutes
Understand how enantiomers can be isolated from a racemic mixture using chromatography with a chiral stationary phase. By Angela Guerrero.