Product News: CHROMABOND® QuEChERS – Special Pre-Mixes for Determination of Pesticides in Food Samples

04 Sep 2009

Since the QuEChERS method was introduced a few years ago it has been readily accepted by many analysts working in the pesticide residue area. The QuEChERS method (Quick Easy Cheap Effective Rugged Safe) involves specially modified silica with primary and secondary amine function (CHROMABOND® Diamino) and removes polar compounds (e.g. organic acids, pigments, sugars) from matrices like fruit or vegetables.
For optimising the extraction of pH-dependent compounds, for minimising decomposition of sensitive substances, and for broadening the matrix spectrum, different modifications of the QuEChERS method have been elaborated.

Aside from a special CHROMABOND® Diamino adsorbent MACHEREY-NAGEL offers a broad range of different QuEChERS Pre-Mixes, containing precisely weighted salts and buffers (e.g. magnesium sulfate, black carbon, C18 silica, sodium citrate or acetate)

Extraction Buffer Mixes: 
- Mix I citrate extraction mix 
- Mix II acetate extraction mix

Clean-up Mixes:
- Mix III for food with low fat content
- Mix IV for samples with moderate content of chlorophyll and carotinoids; e.g. carrots or lettuce
- Mix V with black carbon for food with high content of chlorophyll and carotinoids; e.g. bell peppers or spinach
- Mix VI with C18ec for samples with higher fat content; e.g. avocados

Advantages of ready-to-use CHROMABOND® QuEChERS Pre-Mixes:
- high-precision weighted mixtures
- high reproducibility
- individual combinations possible
- economical, because less time- and personnel-consuming