Table 4. PNT Stability data and dilution integrity in plasma matrix under different conditions.

Nominal Concentration(ng.mL−1)	Mean (ngmL−1)	Recovery %	Precision (CV %)	Accuracy (RE %)
Room Temp. for 8h
20	20.28	101.40	2.12		1.41
150	147.77	98.51	1.37		-1.49
300	298.54	99.51	0.67		-0.49
Three freeze-thaw cycles
20	19.81	99.05	2.38		-0.94
150	147.86	98.57	1.09		-1.43
300	299.61	99.87	1.22		-0.13
Stored at 4 o C for 24 h
20	20.29	101.45	2.17		1.46
150	147.87	98.58	1.57		-1.42
300	298.83	99.61	1.01		-0.39
Stored at -20 o C for 30 days
20	19.62	98.10	1.65		-1.90
150	147.76	98.51	1.21		-1.49
300	298.93	99.64	0.96		-0.36
Dilution integrity
180	176.49	98.05	1.63		-1.95
360	358.28	99.52	1.77		-0.48