Simultaneous Determination and Stability Analysis of Ten New Psychoactive Substances including Synthetic Cathinones, Phenethylamines, and Ketamine Substitutes in Urine Using Liquid Chromatography-Tandem Mass Spectrometry

Figure 3

The stability of phenethylamines and ketamine substitutes in different matrices and temperatures. The stability of (a) para-methoxyamphetamine (PMA), (b) para-methoxymethamphetamine (PMMA), (c) deschloroketamine (DCK), and (d) 2-fluorodeschloroketamine (2-FDCK) in 50% methanol/water (50% MeOH), 50% methanol/water with 0.1% formic acid (50% MeOH in 0.1% FA), and urine at −20°C, 4°C, and 25°C.

(a)

(b)

(c)

(d)