## 3 Results and Discussion
### Analysis of Real Samples
#### 3.2.2 Amphetamine Samples from Contaminated Glassware  
Further practical measurement experience was gained, by analysing residues on equipment of an amphetamine synthesis. For this investigation the Leuckart method for synthesising amphetamine was chosen. This was done by a four-step reaction [15; 16; 17]. The first step was the conversion of APAAN into BMK with concentrated sulphuric acid and water. The generated, BMK containing, organic phase was afterwards mixed with formamide and formic acid, without purification (Leuckart step 1). The thereby generated, NFA containing, organic phase was once more utilised without further purification, and mixed with concentrated hydrochloric acid and neutralised after the reaction was finished (Leuckart step 2). The last step was the precipitation of amphetamine sulphate with the aid of sulphuric acid. In addition to both Leuckart step residues and accrued aqueous waste was investigated. For all three samples, the pre-precursor APAAN, the precursor  
Figure 2: **(A)** Sampled areas are (left to right): drying cabinet, wall and Büchner funnel, all marked with red rectangles. (B) Positive IDTs of the sample areas (indicated by two bars) at **(A)**. Results are (from up to down): Büchner funnel, drying cabinet and wall. **(C)** IMS measurements of the three sampling sports. IMS plasmagrams are in the following order (left to right): drying cabinet, wall, and Büchner funnel. MDMA signal at around 9.8 ms. **(D)** Positive CI mass spectra of the three sampling spots. Spectra are in the following order (left to right): drying cabinet, wall, and Büchner funnel. The signal of 194 m/z is related to the molecular ion peak [M + H] and 163 m/z corresponds to [M-HN-CH3].  
BMK, the intermediate NFA and the product amphetamine were investigated. Table 3 summarises all observed results. For the first Leuckart step, only NFA was detected positively with IMS and APLD-MS. The other substances gave no signal, either due to low abundancy or because the technique is not suitable to analyse them. For the second Leuckart step, all three techniques were able to detect amphetamine. Additional traces of NFA were only detected with APLD-MS. Analysis of the aqueous waste resulted in positive detection of amphetamine for all three techniques. In comparison to this, BMK was found with APLD-MS only. While synthesis waste can be commonly found at clandestine laboratories, the executed measurements indicate that they can be difficult to analyse on-site. The observed difficulties could be related to the complexity of the mixtures and the concentration differences of the analytes. Overall, IDTs were able to correctly detect amphetamine regarding the laboratory analysis results. IMS was able to detect amphetamine and in addition, NFA at Leuckart step one. Most analytes were detected with APLD-MS, the observed analytes are amphetamine, NFA, and BMK. Therefore, these practical measurements indicate similar findings as the practical samples from Section 3.2.1. Within the limitations of a technique, all techniques deliver useful information for the presence of target compounds. In addition, the more complex and sophisticated a setup is, the more information can be obtained.