Effects of Storage Temperature and Time on Stability of Serum Tacrolimus and Cyclosporine A Levels in Whole Blood by LC-MS/MS

Table 1

The cyclosporine A and tacrolimus levels of the samples stored under different storage conditions.

Sample	Cyclosporine A; (mean ± SD); (ng/mL) ()	Percent change; (%)	Tacrolimus; (mean ± SD); (ng/mL) ()	Percent change; (%)
Immediately analyzed (baseline value)	417.66 ± 449.02^a,b,c		7.69 ± 2.62^a
Kept 24 hours at room temperature	377.09 ± 398.69	−9.71	5.16 ± 1.84	−32.89
Kept 24 hours at +4°C	499.02 ± 520.05	19.47	6.63 ± 2.29	−13.78
Kept 48 hours at +4°C	481.90 ± 485.28	15.38	6.89 ± 2.95	−10.4
Stored at −20°C for one month	401.67 ± 421.58	−3.82	7.62 ± 4.45	−0.91

for tacrolimus and for cyclosporine A when compared with the samples kept 24 hours at room temperature.
when compared with samples kept 24 hours at +4°C.
when compared with samples kept 48 hours at +4°C.