Table 2. List of Some of the Impurities Identified in the pH 10.5 Extract of Methamphetamine Synthesized by the Leuckart Route^a.

no.	RT	impurity extracted at pH 10.5	semiquantitative concentration mg/mL	intra-batch (n = 6) RSD	inter-batch (n = 20) RSD
1	7.126	Acetic acid	1 × 10−2	34%	74%
2	9.156	Amphetamine	3 × 10−2	80%	67%
3	10.828	N-(1-Methyl-2-phenylethylidene)methenamine	3 × 10−3	17%	104%
4	11.048	Dimethylamphetamine (DMA)	7 × 10−4	30%	103%
5	13.672	N-Formylamphetamine	2 × 10−3	28%	76%
6	14.331	Bibenzyl	1 × 10−3	71%	114%
7	14.592	N-Formylmethamphetamine*	5 × 10−3	62%	98%
8	15.031	N-Acetylmethamphetamine*	3 × 10−4	42%	48%
9	16.286	Dibenzylketone*	3 × 10−4	102%	115%
10	17.917	3,4-Diphenyl-3-buten-2-one*	2 × 10−4	30%	237%
11	18.043	α-Benzyl-N-methylphenethylamine*	7 × 10−4	39%	164%
12	18.116	Benzylmethamphetamine	7 × 10−5	34%	229%
13	18.221	3,4-Diphenyl-3-buten-2-one*	9 × 10−3	28%	180%
14	18.461	N-β-(Phenylisopropyl)benzyl methyl ketimine*	4 × 10−4	22%	106%
15	18.608	α,α-Dimethyldiphenethylamine*	3 × 10−4	30%	131%
16	18.649	α,α-Dimethyldiphenethylamine*	2 × 10−3	32%	136%
17	18.858	N-Methyldiphenethylamine*	5 × 10−3	33%	94%
18	19.904	N-α,α-Trimethyldiphenethylamine*	3 × 10−3	28%	87%
19	19.988	N-α,α-Trimethyldiphenethylamine*	2 × 10−2	28%	82%
20	20.186	N-Benzoylamphetamine	9 × 10−3	29%	66%
21	20.406	N-Benzoylmethamphetamine	1 × 10−3	35%	75%
22	21.065	2,6-Dimethyl-3,5-diphenylpyridine*	2 × 10−5	48%	58%
23	21.211	Pyridine 7 and 14*	2 × 10−5	32%	78%
24	22.34	N,N-Di-(β-phenylisopropyl)formamide	2 × 10−5	30%	142%
25	23.25	N-Methyl-N-(1-methyl-2-phenylethyl)-2-phenylacetamide*	1 × 10−5	40%	262%

^aRSDs were calculated using peak areas normalized to the sum of the CHAMP target impurities present in the relevant chromatogram. Route specific impurities for the Leuckart route are emboldened, and CHAMP target impurities are marked with an asterisk (*).