Stability of Biological Samples

Some groups of compounds undergo interconversion reactions thus special precautions must be taken when analyzing acylglucuronides, lactone, and open-hydroxy 

The type of anticoagulant used during collection of the blood sample may also affect the stability of drugs tested for or their metabolites. Various chemical agents, such as EDTA, formic acid, acetic acid, sodium fluoride, lithium heparin, potassium oxalate, and methylacrylate have been used to stabilize analytes in biological matrices.  

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