Table: 4.

Stability of HPPH in rat plasma at QC levels

Stability	Nominal concentration (ng/mL)	Measured Concentration (ng/mL) ± SD	Precision (% CV)	Accuracy (% bias)
0 h (for all)	250	245.69 ± 9.99	8.769	−1.721
	400	418.64 ± 13.60	1.534	1.865
	4000	4014.40 ± 17.33	0.446	0.446
	7000	6828.61 ± 13.17	0.197	0.197
Autosampler (48 h)	250	252.61 ± 9.50	3.764	1.045
	400	399.97 ± 10.89	2.724	−0.007
	4000	4024.67 ± 43.62	1.083	0.616
	7000	7097.39 ± 53.22	0.749	1.391
Bench-top (24 h, RT)	250	268.18 ± 14.88	5.549	7.275
	400	395.85 ± 25.49	6.439	−1.036
	4000	3989.07 ± 60.16	1.510	−0.448
	7000	7018.01 ± 56.12	0.799	0.257
Freeze-thaw (−80 °C,	250	244.77 ± 6.88	2.814	−1.629
3 cycle)	400	423.08 ± 21.44	5.069	4.872
	4000	4044.84 ± 58.36	1.443	1.590
	7000	7076.22 ± 39.83	0.562	1.007
Short-term (−80 °C,15 days)	250	232.46 ± 5.35	2.302	−7.013
	400	369.33 ± 5.50	1.491	−7.666
	4000	4069.00 ± 34.07	0.837	1.725
	7000	6974.00 ± 28.79	0.412	−0.371
Long-term (−80 °C, 3 months)	250	245.80 ± 15.46	6.293	−1.680
	400	372.33 ± 13.57	3.646	−6.916
	4000	3972.33 ± 79.14	1.992	−0.691
	7000	6870.67 ± 27.06	0.393	−1.847