Special Topics
Performing cool on-column injection onto 250-µm and 320-µm columns
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Checking the needle-to-column size
You need to check the needle-to-column fit because some manufacturers 
provide columns with internal diameters that are too small. You will bend the 
syringe if you try to inject into a column that is smaller than the needle.
You use the insert that is the same size as the syringe needle you will use in the 
analysis to verify that the column you plan to use is the correct size.
1. Identify the correct insert by the number of rings on it using the table 
below. The syringe needle size is listed to guide you in the choice of 
needles. Some of the needles listed have syringe barrels attached; some do 
not.
Figure 74. Consumables for automatic injection
Column Size Insert Syringe Needles
250 µm
Part no. 19245-20515
6 identification rings
26/32 tapered
320 µm
Part no. 19245-20525
5 identification rings
26/32 tapered
530 µm Polyimide-coated
Part no. 19245-20580
0 identification rings
23/26 tapered 
or
26 straight