In this article we will discuss one of the two methods we use to measure residues of solvents and pesticides, LC-MS-MS. It is advised to first read about HPLC-MS before starting with this article. The basics of LC-MS-MS are equivalent to those of HPLC-MS. Then, in this article we will explain about the additional value of LC-MS-MS for the profiling of pesticides and residues of solvents.
Elsewhere on this website you will also find an article about the other method we use to profile pesticides and solvent residues, GC-MS-MS.
What is LC-MS-MS?
The LC in LC-MS-MS, stands for liquid chromatography. We are using a variant of this technique for the profiling of (HPLC-MS) of active ingredients in plants and herbs as well. Elsewhere on this website you will find the explanation of this method. The HP part in the abbreviation LC-MS-MS is omitted, but in fact it does make use of high pressure (HP) to do its work. The main difference between HPLC-MS and LC-MS-MS is that a more extensive mass spectrometer is used in LC-MS-MS. The MS which is used in LC-MS-MS is called a triple quadruple MS. This spectrometer consists of three parts. In the first part a selection of molecules is already made. By doing this a lot of molecules that we are not looking for can already be “filtered out” from the sample. In technical terms we call this an improvement in the signal/noise ratio. Subsequently, the molecules are bombarded with electrically-charged particles in the next part of the detector (exactly as we have already described in our explanation of HPLC-MS). Then finally, in the third part of the detector, the molecules are definitively measured. Because we already made a selection of molecules earlier in the process a much clearer picture of the different components is realized.
What does LC-MS-MS bring us?
With LC-MS-MS we can detect a large amount of pesticides and components of pesticides (several hundreds). In addition to the identification of these components, we can also determine in what quantity they are present, even if these numbers are very low. The same applies to residues of solvents.
For the profiling of some other pesticides GC-MS-MS works better. That’s why we use both methods.
After performing GC-MS-MS and LC-MS-MS you know which pesticides and solvents are present in your product. This allows you to check whether your product is clean and safe enough for consumption. Also read our article about GC-MS-MS.
By clicking the link below you’ll be able to see a list of all pesticides we can test your sample on.List of pesticides