Applied Biosystems 7900HT - Page 356

DRAFT
September 1, 2004 11:39 am, App_Theory.fm
Appendix D Theory of Operation
D-10 Applied Biosystems 7900HT Fast Real-Time PCR System and SDS Enterprise Database User Guide
Rearranging gives the following expression:
The final step is to divide the X
N
for any sample q by the X
N
for the calibrator (cb):
where:
For amplicons designed and optimized according to Applied Biosystems guidelines
(amplicon size <150 bp), the efficiency is close to 1. Therefore, the amount of target,
normalized to an endogenous reference and relative to a calibrator, is given by:
∆∆C
T
= ∆C
T,q
– ∆C
T,cb
X
N
K1E+()
C
T
∆–
×=
X
Nq,
X
Ncb,
---------------
K1( E)
C
Tq,
∆–
+×
K1( E)
C
Tcb,
∆–
+×
--------------------------------------------- -
1( E)
C
T
∆∆–
+==
2
C
T
∆∆–