| Stability (%) |
| Nominal Level (pg/ml) |
*Saliva samples |
**Stock Solution |
| Unprocessed |
Processed |
Freeze –Thaw Cycle |
|
|
| 24 hrs |
8 weeks |
24 hrs |
48 hrs |
24hrs |
8wks |
|
RT |
-20°C |
RT |
-20°C |
1 |
2 |
3 |
RT |
-20 °C |
| 60 |
105 |
105 |
94 |
102 |
102 |
103 |
102 |
|
|
| 200 |
106 |
111 |
107 |
92 |
95 |
97 |
91 |
102 |
111 |
| 360 |
101 |
99 |
102 |
94 |
90 |
89 |
94 |
|
|
Stability (%)=mean measured concentration (n=5) at the indicated time divided by the mean measured concentration (n=5) at baseline x 100. *Spiked saliva samples were
processed and analyzed immediately (baseline, data not shown), after 24 hours at room temperature (24 hrs RT), after freezing at –20ºC for 8 weeks (8 wks –20ºC), or
after 1 to 3 cycles of freezing at –20ºC and thawing at room temperature (freeze-thaw), or processed and then analyzed after storing for 24 hours at room temperature (24
hrs RT) or 48 hours at –2ºC (48 hrs -20ºC).** Stock solution, 100 μg/mL in methanol |
