Table 6.

Stability of FDB and CFB. Percentage of the remained drug (% remained) was calculated by comparing mean concentrations of the treated samples to the untreated samples in triplicate (n=3); RSD represents relative standard deviation for the treated samples.

Conditions		FDB		CFB
In autosampler vial, 22–25 °C		% remained	RSD, %	% remained	RSD, %
24hr Low(6/0.6ng/mL)		98	6.1	102	7.9
High(700/70ng/mL)		109	1.9	104	2.6
96hr Low(6/0.6ng/mL)		84.2	1.3	106	4.3
High(700/70ng/mL)		95.6	3.6	87.7	1.3
In plasma, 22–25 °C, 72hr
Low(6/0.6ng/mL)		98.6	1.7	100	4.8
High(700/70ng/mL)		107	3.1	107	3.1
3 Freeze-thaw cycles
Low(6/0.6ng/mL)		97.8	7.2	91.7	5.2
High(700/70ng/mL)		97.1	3.7	106	5.4
plasma 2 months, −70 °C
Low(6/0.6ng/mL)		103	2.5	108	9.5
High(700/70ng/mL)		105	0.9	106	3.2
Stock in 25% MeCN, 2 months, −70 °C		99.8	4.1
IS in water, 8 days, 22–25 °C		99.7	3.3