Frequently asked questions about QuEChERS products in experiments(part 3)
Q: What is the difference between the QuEChERS purification technology and the homogenizer after pumping through the suction filter bottle, and then purifying the sample by rotary evaporator and nitrogen blowing treatment? Can QuEChERS purification technology reduce steps and increase efficiency?
A: Use these steps to evenly “paste the filter with a suction filter and then purify the sample by rotary evaporator and nitrogen blowing treatment” to pre-process the sample. First, these steps have no purification function, and are all steps of extraction and concentration. Second, these steps can be very cumbersome. The use of rotary steaming and nitrogen blowing is very time consuming and laborious, and is very disadvantageous for improving sample throughput. The QuEChERS method step is very simple, using the matrix-dispersive solid-phase extraction technique and the high sensitivity of the mass spectrometer to eliminate the sample concentration step (not absolute); and in view of the compatibility of acetonitrile and some instruments, solvent conversion is generally not required. Conventional pretreatment methods use a large amount of solvent to extract the target compound, and then spend a lot of time to concentrate. These are well avoided in the QuEChERS method. The sample used in the QuEChERS method: the extraction solvent ratio is usually 1:1. The relationship (data validation, for high-humidity samples, the majority of pesticides used in this ratio can be guaranteed), which reduces the step of sample concentration.