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 3

Calculated detection limits for ketamine and pethidine in urine.

Analytes	LOD (μg·L^−1)	Slope	Intercept	R^2	EF^a	RR (%)^a	RSD (%)^a,b
Ketamine	0.65	0.0145	0.5112	0.98	108	88.4	5.26
Pethidine	0.91	0.0105	0.1549	0.99	94	92.7	7.38

^aEnrichment factor (EF), relative recovery (RR), and relative standard deviation (RSD) were obtained at the 10 μg·L⁻¹ level of ketamine and pethidine in urine. ^bn = 5.