Summary
The process of LC-MS/MS Quantification analysis is very important. If you want to get the exact data from your experiment, you can follow these tips to get it. Here I will share the experience in LC-MS/MS method with you.
Body
There are six steps you have to do.
The first step---Q1 Scan. This is to ensure the mass of the precursor ion. We will select the polarity, which will be analyzed, ESI/APCI according to the nature of the test compound. And then we choose the scanning range and time, depending on molecular weight. There is one thing you have to keep in mind that the mass of the precursor ion should be more accurate.
The second step is product ion scan. This is to determine the mass to charge ratio of ion. After the first step, we will get the high-quality chart of MS2, the most proper strength of the parent ion is one third or a quarter of the peak in the chart.
The next step is optimizing compound parameters. We can build MRM ion pairs according to the parent ion and ion we chose before. And the analysis time of each pair should be allotted properly. And then we optimize parameters of compound and CAD. The MRM method is initially established. In order to get the most exact result, we generally optimize twice.
The following step is to change the method (that is to say we can change the continuous feed volume method to LC-MS method). In this step, we have to turn off all mass spectrometry interface and MS system, and then to activate LC-MS and MS equipment.
The fifth step is optimizing source parameters with FIA. We can dulute the sample solution to 100 times or 1000 times. After that we can process the FIA analysis. To click the Quantitative Optimization twice. According to the guidelines to start the automatic optimization.
The last step is to optimize the chromatographic conditions. In this step, we have to check the separation condition with the proper concentration samples, balancing the columns. According to the separation condition of MS, gradient elution will be built up.
These are six steps in the LC-MS/MS Quantification methods. Of course, after the experiment, organizing data is really important. You can find the method out to share with us.