Originally designed to analyze fruits and vegetables, QuEChERS now includes a variety of products. Since being developed and released by scientists at the United States department of agriculture in 2003, QuEChERS has gained increasing popularity as a method of selection. It combines several sample preparation steps and extends the range of analytes recovered by older boring extraction methods. The growth of QuEChERS benefits from the emerging requirements for the determination of trace analytes in high-throughput environments.
The matrix includes:
• animal products – meat, fish, kidneys, chicken, milk, honey
• grains and cereal products
• food – wine, fruit juices, fruits and vegetables
The matrix includes:
• animal products – meat, fish, kidneys, chicken, milk, honey
• grains and cereal products
• food – wine, fruit juices, fruits and vegetables
The extension of the QuEChERS method not only demonstrates its function in sample extraction and purification, but also addresses concerns about detecting large quantities of pesticides, herbicides, fungicides, antibiotics, and other compounds throughout the food supply.
The basic form of QuEChERS consists of three steps:
1. Liquid microextraction
2. Solid-phase cleaning
3. LC/MS/MS or GC /MS analysis
The basic form of QuEChERS consists of three steps:
1. Liquid microextraction
2. Solid-phase cleaning
3. LC/MS/MS or GC /MS analysis
QuEChERS continued to improve the sample preparation of analytes in various samples. QuEChERS has now become a generic technology, with many modifications, each variant designed to do one thing: rapid sample extraction and clean up.
These modifications include:
• increase the flux of samples while reducing the cost
• minimize degradation of susceptible compounds, such as base and acid-unstable pesticides
• extend the range of matrices applicable to this approach
These modifications include:
• increase the flux of samples while reducing the cost
• minimize degradation of susceptible compounds, such as base and acid-unstable pesticides
• extend the range of matrices applicable to this approach
Three main QuEChERS approaches
1) the original QuEChERS method (by Anastassiades, Lehotay et al.)
• sodium chloride is used to reduce polarity interference
• provides the cleanest extraction because it USES less reagent
• does not use acetic acid that may be problematic in GC/MS analysis
• dispersive clean-up procedures are used
1) the original QuEChERS method (by Anastassiades, Lehotay et al.)
• sodium chloride is used to reduce polarity interference
• provides the cleanest extraction because it USES less reagent
• does not use acetic acid that may be problematic in GC/MS analysis
• dispersive clean-up procedures are used
2)AOAC 2007.01
• use 1% acetic acid in acetonitrile and sodium acetate buffers to protect base-sensitive analytes from degradation
• a USDA study showed that this method provided an excellent recovery rate for ph-sensitive compounds compared to the other two QuEChERS methods
• the method uses acetic acid in the extraction step. Acetic acid may overload the PSA adsorbent used in the purification process, rendering it ineffective and possibly causing GC separation problems
• use 1% acetic acid in acetonitrile and sodium acetate buffers to protect base-sensitive analytes from degradation
• a USDA study showed that this method provided an excellent recovery rate for ph-sensitive compounds compared to the other two QuEChERS methods
• the method uses acetic acid in the extraction step. Acetic acid may overload the PSA adsorbent used in the purification process, rendering it ineffective and possibly causing GC separation problems
3) EN 15662
• European methods include sodium chloride to limit polarity interference, and several buffers to retain alkali-sensitive analytes
• sodium hydroxide should be avoided in the citrus step as it may increase impurities in the extract and damage the adsorbent used in the purification step
• European methods include sodium chloride to limit polarity interference, and several buffers to retain alkali-sensitive analytes
• sodium hydroxide should be avoided in the citrus step as it may increase impurities in the extract and damage the adsorbent used in the purification step
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