How to Set Up Bottom Sensing in High Performance Autosamplers and Well Plate Samplers

Answer

This Information Applies To: Agilent high performance autosamplers, and well plate samplers G1368A, G1377A, G1367A/B/C/D/E, G4226A, and G5667A

Issue

The bottom sensing feature in Agilent OpenLab Software is used to detect depths of vials or plates. Material of plates or vials must be able to resist the force of the needle; not all vials are suited.

Requirements

Compatible consumables for bottom sensing feature (Figure 1):

• Glass vials without inserts (such as 5182-0714)
• Glass vials with fixed inserts (such as 5188-6591)
• Glass vials with inserts without polymer feet (such as 5183-2090)
  

  
  Figure 1. Compatible vials

Incompatible consumables for bottom sensing feature (Figure 2):

• Glass vials with inserts containing polymer feet (such as 5183-2088), as it could affect injection precision
• Polypropylene vials (such as 5182-0567), as it could lead to clogging of the needle
• High-recovery vials (such as 5183-2030) nor with micro-V (such as 5184-3550), as it could damage the needle tip
  
  
  Figure 2. Incompatible vial
  

Steps to Follow

The Vial/Well Bottom Sensing feature allows the needle to detect nonuniform well bottoms and adjusts the depth of the needle position above the detected bottom of the vial or well. You can use this feature in combination with the Draw Position to customize the draw position of the needle.

Right click the sampler, select Method, under Advanced > Auxiliary, check the box Vial/Well bottom sensing to turn on this feature (see Figure 3). The default setting is cleared:

• When Vial/Well Bottom Sensing is disabled, the offset is calculated from the stored dimensions of the plate.
• When Vial/Well Bottom Sensing is enabled, the offset is calculated from the bottom position determined by the bottom sensing of the instrument.

Draw Position

The Draw Position is a vertical offset that enables you to position the needle a specific distance (in mm) away from its standard position. The Draw Position offset is calculated from the bottom of the well, with a slight amount of clearance to cover tolerances.

• The default position (Draw Position = 0.0) is a vertical offset of +1.0 mm.
• Use a negative offset to touch the well bottom with the needle
• Use a positive offset to raise the needle higher in the well to clear precipitates on the bottom of the well, or to select on phase of a biphasic sample.
  
  
  
  

  
  Figure 3. Method Setup Parameters in High Performance Autosampler or Well-Plate Sampler
  1. Sampler icon, 2. Method, 3. Advanced > Auxiliary, 4. Draw Position and Vial/Well bottom sensing, 5. Ok button

Table 1 shows needle tip position when draw position/ offset = 0  ​​

Tips: You may want to turn off Vial/Well Bottom Sensing to increase speed of injection, or to avoid the needle touching the bottom of the well if a sample precipitate could clog it.

Learn how to effectively operate your Agilent samplers: 1290 High Performance Autosampler InfinityLab LC Series user manual on Agilent.com 1260 Bio-inert High Performance Autosampler InfinityLab LC Series user manual on Agilent.com