Local conversion of redox inactive molecules into redox active ones: A formaldehyde based strategy for the electrochemical detection of illicit drugs containing primary and secondary amines

Electrochemical detection of MDMA and 2C-B in ecstasy tablets using a selectivity enhancement strategy by in-situ derivatization

“…Note that the selectivity towards 2C-B is achieved by requiring the presence of both the peak at 0.95 V and the peak at 1.14 V after derivatization. In line with earlier work by Schram et al [27] the observed reaction was proposed to be a Eschweiler-Clarke methylation whose reaction scheme is shown in Fig. S2.…”

“…An electrochemical pretreatment has proven to be successful in the past for similar cases [26], however a more appealing approach is an in-situ derivatization of one of the target compounds. Schram et al recently reported the in-situ methylation of the primary amine of amphetamine using formalin to convert the redox inactive amphetamine into the redox active methamphetamine and dimethampetamine [27]. A similar opportunity arises here, as 2C-B contains a primary amine while MDMA does not.…”

“…Parrilla et al [26] introduced a derivatization approach to convert electrochemically inactive amphetamine into a detectable secondary amine by derivatization with 1,2naphthoquinone-4-sulfonate. Another approach to enrich the electrochemical fingerprint (EF) of primary amines was introduced by Schram et al [27] In this study, those functionalities were converted into their redox active N-methylated and N-dimethylated species by reaction with formaldehyde. This strategy has also been used in this work to discriminate between MDMA and 2C-B.…”

Electrochemical methods for on-site multidrug detection at festivals

“…To overcome this, derivatization approaches using various reagents have been reported. 47–50 For example, the formaldehyde approach developed in our group successfully employs pH7F buffer (containing 30 v% formalin solution) to detect amphetamine and enrich the EP of other drugs with additional characteristic peaks. 48…”

“…To overcome this, derivatization approaches using various reagents have been reported. [47][48][49][50] For example, the formaldehyde approach developed in our group successfully employs pH7F buffer (containing 30 v% formalin solution) to detect amphetamine and enrich the EP of other drugs with additional characteristic peaks. 48 When multiple target compounds have to be detected by the same single sensor, this strategy becomes cumbersome due to potentially overlapping peaks.…”