Chromatography Forum

Hi,
there are many tubing sizes from manufactures (both internal and outside diameter), so I'm wondering what are typical tubing ID for analytical, semi-preparative and preparative HPLC? Does it scale up with the flow rate when you scale up from analytical to semi and to preparative? It's look like 1/16" OD is typical mainly for analytical application but not sure about ID. Manufactures sell from 0.005 to 0.040". Any help will be appreciated.
Thanks,
Veronika

For regular HPLC (not UHPLC). 0.020" is a nearly ubiquitous ID. Some prefer a bit narrower bore on either end of the column.

I normally use 0.010" tubing for all connections from injector to column to detector and detector exit, both for analytical and semi-prep up to 5 mL/minute flow rate.
On many older HPLC instruments, 0.040" SS is used for plumbing on and between pumps.

The outside diameter is not that important, and as your recognized 1/16" is mostly used.
The inner diameter on the other hand has a significant influence on performance.

the biger the ID the more dead volume you will have.
Which in terme influences the analysis time and the peak shape.
So for analytical application I usually go for smaller ID.
Of course a smaller ID will give you higher back pressure.
In this regard you will also have to think about the material you are using
simple PEEK tubing (up to 200 bar) or Steel Cappillary tubing (up to the column max. pressure)

If i can i am going for easy to handle PEEK tubing.

For analytical purpose I most of the time use 0.005".

Be carefull about the tubing ID and lenght for detector outlet ( waste )
For analytical UV detectors do not use narrower tubing than 0.01'' and more than 1 meter otherwise the backpressure may be harmful .

For RI detectors wider tubing ID required such as 0.02'' or more.

Thank you all for the suggestions!!!
Initially I'm planning to do analytical HPLC to optimize conditions for separation but later I need to scale it up. What tubing ID would you recommend for flow rates I estimate to be ~30ml for the preparative HPLC with 50mm ID x 50cm length column?