Chromatography Forum

Hi!
I'm searching a capillary column connector for connect my retention gap with my main column.
Presently, the best system i have found is the butt connector from Supelco (Sigma-Aldrich) but Supelco have some problem with delivery...3 months for my last call.....service is
What is your choice for column connection?.....i don't want glass connector
Thank

Hi Rick,

I use Press-fit connectors most of my times. I did try using kind of butt connectors with ferrules, etc claiming to have better seal but eventually I still stick to the Press-fit ones 'cos it is easy to change the retention gaps and cheaper price. There are two types of "glass" for this connector. Choose fused silica instead of borosilicate glass since the latter, I guess, may have different expansion coefficient c.f. to your capillary columns which in turn may pierce the polyimide seal during oven temp. ramp.

Hubert

Another press-fit connector user here. It takes a bit of practice - but once you get the technique down, they work well.

I use presstights, why don't you want to use them ?

Peter

For hydrogen as carrier gas and high temperatures I used the supelco connector. The press-tights simply started to leak at temperatures above 300 degrees C. We even had an explosion due to a leaky press-tight. For helium and lower temps press-tight is OK.

(Later for determination of mineral oils in water with on-column injection I changed to a 0.53 mm column with no retention gap at all.)

I use glass press-fit and butt connectors depending on the situation. If you are having problems with the press-fits you could use the more gimmicky press-fits that Restek supply. They have a clamp in additon to the glass connector to keep everything in place. Part number is 21106 for 0.32mm ID columns.

Rich

Thank you for your comments
I don't use glass connector....i hate leak and the Vu-unions from Restek is very expensive.
SGE have a mini-union with Sit-tite ferrule....i don't know if this product is good but the price is ok....do you know?

I don't know if a representive from Supelco is on this web site but Supelco have ship my butt connector ferrule 1 day after this message

Have a good week-end

Definitely a technique to using the glass connectore

I think a good clean cut with no burrs id the key, and a short bake to vapourise the solvent and create a good seal.

BTW, does anyone here silanise glass connector? Does it make much difference to chromatography?