[synthon]

Something which has bothered me for a while is cutting aluminum TLC plates with one crooked edge.  This inevitably leads to solvent creeping up one side faster than the middle and can make the spots run together in extreme cases.  I've adjusted to this by raising the spotting line, and spacing the lanes further, but is there a better way to get more consistently cut plates?  Cutting techniques?  Recommended scissor styles/brands maybe?  I'm typically using some heavy, metal scissors but have used plastic ones with similar results.  Maybe it's necessary to keep the blades sharp?

I found a pair of scissors which are supposedly designed for TLC cutting which look interesting,

https://extranet.fisher.co.uk/webfiles/uk/web-docs/0341_LC.pdf

and also this page describing 'proper technique',

http://www.erowid.org/archive/rhodium/chemistry/equipment/tlc.plate.cutting.html

but nothing there is new to me.


It's not a disruption to my work so I haven't really pursued it before, but it sure would be nice to have cleaner looking TLCs.  Does anyone have better tips than those in the links?

[discodermolide]

Use a guillotine as in the French revolution, works wonders. And you can cut several at once.

[Dan]

I taper the bottom edge (i.e. cut off the bottom corners) to compensate for the problem of the solvent moving faster at the edges.

[willug]

It depends on the quality of the TLC plates too. Some just seem to fall apart no matter how careful you are.

[PhDoc]

The guillotine idea is a good one. If you don't have one, try using a razor blade or Exacto knife with a straight edge. If there's any way you can get the glass plates, you'll be much better off.

[synthon]

Razor blade, yes!  Works much better than my scissors.  I don't know why I hadn't tried that before, but I had no faith in that working as well as it did.  The cut still raises the silica somewhat, but over a much smaller area making the capillary effect less noticeable.  Also, I had trouble finding a guillotine style anywhere (not that I would be able to get one ordered) does anyone have a link to one?

[discodermolide]

Use a paper cutting guillotine.
Manipulate the cutting leaver slowly so as to cause excruciating pain to the TLC plate. If you do this you will get a clean cut.
Watch out for your fingers.

[PhDoc]

What type of surface are you using to cut your TLC plates on?

When I was a Postdoc, I had to use those cheap aluminum plates. Hated them. Fortunately it was for alumina only. I placed the aluminum sheet coated side face down onto a clean [thick] glass surface, then used the razor blade and straight edge method to cut.

It's been a LONG time since doing this, so I don't recall having so many problems with elution.

[ATMyller]

I found a pair of scissors which are supposedly designed for TLC cutting which look interesting,

Also known as Fiskars kitchen scissors
https://www.amazon.co.uk/Fiskars-9874o33-Kitchen-Scissors-Right/dp/B000297TJ4

I use paper guillotine against a wooden board.

[PhDoc]

Please try the clean thick glass surface.

[curiouscat]

And you can cut several at once.

Did the French ever try that too?

[discodermolide]

I think they may have had a tricyclic model, although I'm not sure.

[curiouscat]

I think they may have had a tricyclic model, although I'm not sure.

Why were the blades angled? Anyone know? Cleaner cut?

[synthon]

Smaller surface area (pressure) on cutting edge, I think.  Think of how you'd saw a piece of wood with a handsaw.

Please try the clean thick glass surface.

I've been using a piece of cardboard which has worked sufficiently, and cutting by hand (no straightedge).  If I find a pane of glass lying around I'll give it a try.