Test Tube Columns from Baran Lab

Post date: Jan 18, 2019 12:11:11 AM

Test Tube Columns from Baran Lab

http://openflask.blogspot.com/2019/01/technique-primer-test-tube-columns.html

excerpt from the page:

We use these columns on crude reaction mixtures from ~10 to ~500 mg scale. For smaller scale than this, we use prep TLC; larger, just a standard reusable column.

To build the column,

for 10-50 mg, we just use a Pasteur pipette as the column.

For 50-200 mg, we build it out of a 16 X 150mm tube.

For 200-500 mg, we build it out of a 25 X 150 mm tube.

For the latter two, the first step is to pull a bottom spout from the test tube. Basically, you heat the tube with a Benzomatic torch, until you see the bottom glow orange and "wilt" slightly. At this point, you grab the glass with a pair of tweezers and steadily pull to make a long stem. It's hard to explain, but easy to demonstrate: