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Restriction Enzyme-EcoR V come frozen !? - (Mar/03/2008 )

Ordered from Roche, it came in dry ice, which should be fine. But when I
open the box, I found the enzyme solution is completely frozen.

The storage buffer contains 50% glycerol, so it shouldn't freeze in dry ice,
right?

Anyone experience this before? I don't want to take the risk to ruin my precious DNA samples.

Just called Roche to ask for a replacement, they said they can't.

-Cathleen-

QUOTE (Cathleen @ Mar 4 2008, 07:36 AM)
Ordered from Roche, it came in dry ice, which should be fine. But when I
open the box, I found the enzyme solution is completely frozen.

The storage buffer contains 50% glycerol, so it shouldn't freeze in dry ice,
right?

Anyone experience this before? I don't want to take the risk to ruin my precious DNA samples.

Just called Roche to ask for a replacement, they said they can't.

Test it once with something replaceable, like a plasmid. If it works, fine, if not tell Roche the enzyme arrived frozen and does not work.

-swanny-

QUOTE (swanny @ Mar 3 2008, 07:27 PM)
QUOTE (Cathleen @ Mar 4 2008, 07:36 AM)
Ordered from Roche, it came in dry ice, which should be fine. But when I
open the box, I found the enzyme solution is completely frozen.

The storage buffer contains 50% glycerol, so it shouldn't freeze in dry ice,
right?

Anyone experience this before? I don't want to take the risk to ruin my precious DNA samples.

Just called Roche to ask for a replacement, they said they can't.

Test it once with something replaceable, like a plasmid. If it works, fine, if not tell Roche the enzyme arrived frozen and does not work.


I aggre with swanny. Once it happened to me but with a t4 polynucletide kinase and it doesn't work. it was from life technologies and they replace it. it shouldn't freeze. Something is wrong, but you can tried it with any not important sample .if it doesn't work roche must change it.!
Good luck!

-marielita-

As suggested, try to cut some not so precious plasmid with thsi enzyme and if this doesnt work, then complain to Roche and threaten that you will never buy from them and also advice your friends about buying from them. If they don't replace, forget everything and buy from NEB.

-scolix-

With 50% glycerol, the freezing point is -23 C. All enzymes shipped on dry ice will be frozen. A small number of freeze/thaw cycles will not damage enzymes -- the reason for keeping them at -20 is to prevent multiple freeze/thaw cycles. Your enzyme will work, unless it has been mishandled in other ways than in shipment.

-phage434-

I have enzymes shipped to me regularly on dry ice and they're always frozen. Even Reverse transcriptases which are more labile enzymes than restriction enzymes, never experienced problems. I'd rather have them shipped to me frozen on dry ice than with freeze packs as you never know how long your enzyme's gonna be travelling.

-vairus-

QUOTE (phage434 @ Mar 5 2008, 06:21 AM)
With 50% glycerol, the freezing point is -23 C. All enzymes shipped on dry ice will be frozen. A small number of freeze/thaw cycles will not damage enzymes -- the reason for keeping them at -20 is to prevent multiple freeze/thaw cycles. Your enzyme will work, unless it has been mishandled in other ways than in shipment.

You're a wealth of knowledge Phage. How long have you been cloning for?

-killerkoz17-