Priming the Syringe (ASI-100 Series)

Autosampler Control
Priming the Syringe (ASI-100 Series)

The PrimeSyringe command allows removing air from the syringe without dismantling the syringe from the instrument. The steps of the PrimeSyringe procedure (see below) are automatically performed 5 times with the wash liquid. Then, repeat the procedure with the eluent.

Before performing the PrimeSyringe command:

Make sure that the pump flow is off. Otherwise, the pump will deliver eluent to the wash vial when the injection valve switches to the Inject position (see step 3 below).
Set the WashSpeed and the DispSpeed to values that correspond to the installed syringe. (Note: When a wash vial is used, the WashSpeed command is required instead of the DrawSpeed command.)

The recommended settings and the required time are listed in the table below:

Syringe	100 µL	250 µL	1000 µL*	2500 µL*
WashSpeed [µL/s]	5	10	25	25
DispSpeed [µL/s]	5	10	50	50
SyringeDelay [s]	5	5	5	5
Duration of the prime syringe cycle [min]	Approx. 5	Approx. 6	Approx. 7 (5 x 1000µl)	Approx. 9 (5 x 2500µl)

* A PrimeSyringe command is not usually required to remove gas bubbles from syringes with a volume of 1000 or 2500 µL. It is usually sufficient to inject the entire syringe volume of eluent.

Fill the wash vial with the wash liquid. Enter the vial position in Chromeleon (WashVial).

Dionex recommends using isopropanol (2-propanol) for the PrimeSyringe cycle and repeating the cycle with the starting eluent of the next sample.

The ASI-100 automatically performs the following steps:

The injection valve is switched to the Load position. The eluent flow is from the pump through the valve directly to the column; the eluent does not come into contact with the needle or the syringe. In addition, the needle descends into the wash vial:

The syringe is completely filled:

The injection valve is switched to the Inject position; the needle remains in the wash vial and the contents of the syringe are directed to waste:

The injection valve is switched to the Load position

The above steps are performed five times. The wash liquid reaches the syringe, removes existing gas bubbles, and exchanges the syringe content:

Tip:

The PrimeSyringe command exchanges the liquid in the autosampler completely. Therefore, you may also use the PrimeSyringe procedure when switching between incompatible applications, such as between reversed-phase and normal-phase applications.

Afterward, the needle returns to the needle port and the injection valve is switched into the Inject position. Although most of the wash liquid is exchanged with the current eluent and the needle and the needle port are filled again with eluent, the segment between the syringe and the waste remains filled with the wash liquid:

Therefore, repeat the procedure using the eluent to precondition the valve and syringe with the eluent, too. (Note: To avoid deposits, use the starting eluent without buffer additives.)