Quantitative analysis using single point internal standard

A single point calibration may be used instead of a working calibration curve for quantitation by either external or internal standard method, if the response from the single point standards produces a response that deviates from the sample extract response by no more than 20%. The solvent for preparing calibration standards should preferably be the same one used to make the final sample extract. Hexane, isooctane, or methyl-feri-butylether is an appropriate solvent for the analysis of chlorinated pesticides by GC-ECD. 

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