Preconcentration and Determination of Psychotropic Drugs in Urine Samples by Ion Mobility Spectrometry with Electrospray Ionization Coupling On-Line Single-Drop Liquid-Liquid-Liquid Microextraction

Table 1

Experimental drift time and reduced mobility constants (K₀)^a for ketamine and pethidine, obtained for each method.

Analytes	Parameter	IMS	SDLLLME	SDLLLME
			In water	In urine
Ketamine	Drift time (ms)	30.64	30.82	30.91
	Mobility	1.47	1.46	1.46
Pethidine	Drift time (ms)	32.43	32.67	32.52
	Mobility	1.39	1.38	1.39

^aReduced mobility are expressed in units of cm²·V⁻¹·s⁻¹.