Analytical Validation of a New Enzymatic and Automatable Method for d-Xylose Measurement in Human Urine Samples

Table 1

Parameters obtained in the analytical validation of the enzymatic D-xylose quantification method.

Parameters	Cobas c502; (Roche)	ILab 600; (Werfen)	Dimension Vista; 1500 (Siemens)
Range of linearity (mg/dL)	0.25 to 15	0.02 to 15	0.25 to 15
Linearity:
	0.9998	0.9996	0.9999
a (AU⋅dL/mg)	0.0610 ± 0.0004	0.088 ± 0.002	0.0285 ± 0.0002
(mg/dL)	0.0006 ± 0.003	0.01 ± 0.01	0.003 ± 0.001
CV	0.0038	0.0144	0.0012
Limits
LoB (mg/dL)	0.046	0.072	0.011
LoD (mg/dL)	0.186	0.490	0.130
LoQ (mg/dL)	0.623	1.640	0.420
LLoQ (mg/dL)	0.850	0.550	0.550
CV
Within-run CV (%)	<3.7	<7.1	<13.6
Between-run CV (%)	<11.5	<3.0	ND
Total CV (%)	<11.8	<7.7	ND
Inaccuracy
Within-run inaccuracy (%)	≤12.0	<9.0	<9.7
Between-run inaccuracy (%)	<5.9	<3.9	ND
Carry-over (%)	3.3	4.0	ND

LLoQ: lower limit of quantification; LoB: limit of blank; LoD: limit of detection; LoQ: limit of quantification; ND: not determined.