Quantitation of Uncalibrated Compounds Using a Fixed Response Factor in OpenLab CDS

Answer

This Information Applies To: Agilent OpenLab CDS 2.x

Issue

This article outlines the procedure on how to quantify the uncalibrated compounds in OpenLab CDS 2.x when the analytical method requires a fixed response factor.

Background

Uncalibrated compounds can be quantified either with a fixed response factor or using the calibration data of one of the calibrated compounds. Quantitation using a fixed response factor or calibrated compound data is signal-specific.

Requirements

The unknown compounds must be added as compound in the Processing Method. This procedure requires a built calibration table. 

Steps to Follow

The software allows you to quantify an identified compound that is based on a fixed response factor (Manual Factor column). The compound amount is calculated according to the following expression:

Amount = Response * Manual Factor
where:
Manual factor: Fixed response factor
Response: It can be Area, Area%, Height, Height%, Rel. Area, or Rel. Amount

1. In the Processing Method, go to Compounds > Calibration (see Figure 1)
2. In the Compound Table tab, set the following parameters for every uncalibrated compound:
   Mode column: select Manual factor
   Manual factor column: Enter the response factor that you want to use (see Figure 1 and Figure 2)
3. Click Reprocess All to see the amount of the uncalibrated compound (Figure 2)

Figure 1: Compound table settings using a manual factor

Figure 2: Quantitation using a manual factor

Using a manual factor with an ISTD method
If the compound amount is quantified using a fixed response factor and ISTD, the following formula is used:

Relative area = Area/ Area_ISDT
Or:
Relative height = Height / Height_ISTD

The amount is the calculated as follows:

Amount = Relative Area * Manual Factor * Amount_ISDT
Or:
Amount = Relative Height * Manual Factor * Amount_ISDT

Dependency of manual factor and response factor (RF)

With RF defined as Response per amount (default setting):
RF= 1/ Manual Factor

With RF defined as Amount per response:
RF = Manual Factor

You can also quantify uncalibrated compounds using a calibrated reference compound. See the article Quantitation of Uncalibrated Compounds Using Reference Compounds in OpenLab CDS. 

Learn how to effectively operate your Agilent OpenLab CDS Software:  HPLC-OLII-1151e - Agilent OpenLab CDS - Quantification e-learning course available from Agilent Education