#column chromatography

[acrylate]

Column chromatography

[crisis-vision]

I got to run my first ever column in my synthetic organic chemistry lab🥼

[circumlocutive]

Some normal phase column chromatography for y'all. We love colored fluorescent compounds! Fuck trying to see where your shit is on a column if it's white or colorless. I also love that I can just shine a UV lamp on the column to find my compound and it'll glow.

Anyway, I'm running it in pure methanol (very polar) and probably eluting some of the silica gel filling the column (polar). This is a pretty wild column to run (but we're doing it anyway because it's what folks did in the literature), since you should use a (relatively) nonpolar mobile phase (like dichloromethane or hexane) with a polar stationary phase (silica powder/gel) to get the (relatively) nonpolar compound off, buuuuuuuut my compound is slightly polar. And it's stuck (this pic is from loading the column but I've run the column w liters of solvent and there's still a distinct stripe that is not moving) and I have precious little of it to fuck around with troubleshooting and transferring around. Like yield is definitely less than 50mg /total/ bro. Like I spent a summer painstakingly making all the precursors that led to this. Like I'm so fucked if I lose any more of it.

What I should do in the future is get reverse phase columns (polar mobile phase, greasy nonpolar stationary phase) so my compound is less likely to get stuck and comes out faster, BUT they're fucking expensive ($$$) and would take forever (like 2-4 weeks) to receive if I ordered them (supply chain issues). :(

So I'm drying the column out and I'm going to tip it upside down and let the sand and silica come out into a round bottom or something and resolvate with methanol and just try and filter it and hope only my product precipitates and all the junk flows through.

[forensicfield]

Chromatography

Chromatography is a physical process of separation in which the components to be separated are distributed between two phases; one phase is stationary phase while the other is the mobile phase moves through it in a definite direction.

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[labphoto]

Chromatogarphic separation of a quite complex reaction mixture. 

Column chromatography is a time and solvent consuming hobby of organic chemists. It is often used when classic methods: crystallization, distillation or solvent-solvent extractions fail to separate the n+1 product what was produced in the flask from a reaction. 

If you are lucky enough the main component will separate, or as in this case partially separate. The first 40 fractions contained the “A” component, from 45 to 55 the mixture of “A” and “B” component, from 56 to 72 the “B” component and after that everything else from “C” to “Z”. 

[justlifeaslarry]

Column Chromatography skills

[soretpeak]

Got the prettiest colored fractions off my column!

[momentsinmed]

February 9, 2017 >> Spent my Thursday morning labeling 40 microcentrifuge tubes for size exclusion chromatography (SEC). SEC involves running a protein sample through a column with microscopic porous beads that trap particles smaller than its pores while allowing larger particles to flow through and elute out first. The eluate is captured in small amounts at a time, separating the sample based on the size of the particles within it. This is one of many methods used for protein purification.