Gilson 402 manual Liquid Mode, Operation - Advanced Use, Additional Information

Operation - Advanced Use 5

Additional Information

Gilson D200 tips are used for volumes from 1 µL to 78 µL (with a 100 µL syringe, minimum recommended air-push-volume is 20 µL). Gilson D1000 tips are used for volumes from 50 µL to 900 µL (minimum recommended air-push-volume is 100 µL).

The liquid is ejected with an Air push volume of at least 20 µL when using a Gilson D200 tip and 100 µL when using a Gilson D1000 tip. An automatic software correction of 2% of the piston stroke

is made to improve accuracy with Gilson D200 and D1000 tips. For example, when using a Gilson D200 tip, if an Air push volume of 20 µL is chosen, the maximum sample volume will be 78 µL; this volume will be handled with the 100 µL syringe. For the dual syringe model, the left syringe operates if the volume exceeds 78 µL; for the single syringe model, an error message is displayed.

A disposable tip should not be fitted, when priming the 402 in ‘Air Mode’. Droplets of liquid adhering the tubing after purging must be wiped from the end, before fitting a tip.

To minimize carry-over, dilution can be performed with one or more tips. If one tip is used, you use the Dilute task where the diluent and the sample are separated by an air gap (volume defined in the Configuration menu). When several tips are used, you use multiple runs of the Dispense task to transfer the liquids, changing the tips where appro- priate: one to aspirate and dispense the diluent, one to aspirate and dispense each sample.

Liquid Mode

You can use this mode in the same way as the standard tip with tapered tubing. However, it is recommended not to use an air gap, or at least to use it in a way that keeps the air gap in the disposable- tip. The use of Gilson D200 tips does not adversely affect the performance of the 402.

The Gilson D200 tip is installed to protect the end of the probe against corrosive chemicals, and by changing the tips within a task.

A disposable tip should be fitted, when priming the 402 in ‘Liquid Mode’. The following flow rates are suggested when priming: small syringes up to 10 mL/ min, larger syringes at least 80 mL/min.

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