Reproducibility of NMR Analysis of Urine Samples: Impact of Sample Preparation, Storage Conditions, and Animal Health Status

Table 1

Overview of samples used for the various experiments of this study.

Sample name	Source	Characteristics	Use
Calibration	Synthetic	10, 100, 1,000, 10,000 µg/mL	Calibration for single metabolite quantification
Accuracy test	Synthetic	Defined composition (mixture of 4 metabolites at different concentrations) in a range of 10 to 10,000 µg/mL	Determination of accuracy of measurement
Stability test	Treatment-wise pooled urine samples (urine from 5 male and 5 female rats per pooled sample)	Treatment with natrosol, furosemide, or HCBD	Determination of effects from; (i) pH and salinity; (ii) Storage (refrigerating, freezing); (iii) Drug treatment
Freeze-thaw test	Treatment-wise pooled urine samples (urine from 2 male rats per pooled sample)	Treatment with natrosol, furosemide, or HCBD	Determination of effects from multiple freeze-thaw cycles
Biological variance test	Urine samples from individual male or female rats	Treatment with natrosol, furosemide, or HCBD	Determination of interindividual biological variance and effects from sample composition on interindividual variance