Presumptive Testing of Amphetamines

How can this confusion which may arise about which drug is present 

This is easily achieved by undertaking positive controls when the presumptive test is attempted on the sample material. Such controls provide direct reference points against which colour changes can be matched. 

Having established that an amphetamine might be present in the sample, the next step is to determine which of this group of controlled substances is present. This can be rapidly achieved by using TLC. 

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