Table 2.

Linearity and LLOQ.

Analyte	Linear range (μg/mL)	Linear equation	r2	Accuracy	LLOQ (μg/mL)
Citrate	40–1000	y = 0.0014x-0.0045	0.9986	93.1%–103 %	40.0
Cystine	4–100	y = 0.0231x-0.0022	0.9998	98.2%–102 %	0.10
Oxalate	10–250	y = 0.0233x+0.0255	0.9988	96.0%–104 %	5.00