Table 2: Table Recovery of PPi spiked into human plasma indicates excellent accuracy of the PPi assay.

Plasma of three individuals was spiked with the indicated amounts of PPi. Afterwards, the total concentration of PPi was determined in the spiked samples. Samples were diluted 1:5 in TE buffer before analysis. Values are based on triplicate determinations.

		Individual 1		Individual 2		Individual 3
Plasma PPi concentration	μM	2.16		1.76		1.39
PPi added	μM	1.00	0.10	1.00	0.10	1.00	0.10
Average PPi concentration detected in spiked plasma	μM	3.13	2.26	2.74	1.86	2.40	1.50
SD	σ	0.04	0.08	0.08	0.03	0.04	0.04
CV	%	1.2%	3.5%	2.8%	1.6%	1.6%	2.6%
PPi recovery (accuracy)	μM	0.97	0.09	0.98	0.10	1.01	0.11

SD, Standard deviation; CV, coefficient of deviation.