How to calculate isoelectric point (pI) when separating proteins by charge profile in Empower - Tip271
OBJECTIVE or GOAL
In Empower, calculate isoelectric point (pI) when using the Maurice to do capillary isoelectric focusing (cIEF) to separate proteins by charge.
ENVIRONMENT
- Empower
- Empower Tip of the Week #271
PROCEDURE
STEP 1
Specify the information for the markers in the Markers section of the Instrument Method Editor (Figure 1).
STEP 2
Specify the values for the makers on the Value tab of the Component Editor (Figure 2).
Custom Fields
STEP 3
Figures 3 and 4 show the properties of the Custom Field PI_Calc and the full equation.
(Figure 3)
(Figure 4)
STEP 4
Figure 5 shows the properties of the Custom Field PI_Slope.
STEP 5
Figure 6 shows the properties of the Custom Field PI_Unknown.
STEP 6
Figure 7 shows the properties of the Custom Field PI_Y_Intercept.
STEP 7
Figure 8 shows the properties of the Custom Field PI_Value.
Processing Method and Results
STEP 8
Specify the names of the markers in the processing method on the Components tab. These names must match the ones in the Custom Fields. If you decide to create an LC Processing Method and use Retention Time rather than a CE Processing Method with Migration Time, you must adjust the Custom Fields accordingly (Figure 9).
STEP 9
Figure 10 shows the calculated result with all fields populated.
ADDITIONAL INFORMATION
This can be done with either the Pro or QuickStart interface.
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