I need help to understand how to work out this formula.
I am really sorry for the duplicate question, but as i have no reputation points i cant comment on any comments others have made and i cant edit, until it's peer reviewed.
** OD is Optical density, so the OD of S is 0.285 so i am assuming OD(s) = 0.285
This is all the information i have been given, if you down vote please explain why. I dont understand why i need 50 reputation points to even reply to a comment.
OD of S = 0.285
OD of P = 0.22
OD of N = 1.464
a = 2.5
b = -0.70
OD(S) - OD(P)
SNc = ---------------
OD(N) - OD(P)
Formula:
Log(Titer) = a + b x Logit(SNc)
or
Titer = 10^(a + b x Logit(SNc))
What is the value of Titer?
Step by step:
$$SNc = \frac {.285-.22}{1.464-.22}=.0522508...$$
Assuming the base of the $Logit$ function is $10$ then we are to compute: $$Titer=10^{a+bLogit(SNc)}=10^a\,10^{bLogit(SNc)}$$
But $$Logit(SNc)=Log_{10}\left(\frac {SNc}{1-SNc}\right)=Log_{10}(.055131467)$$ Hence $$Titer=10^{2.5}\,(0.055131467)^{-.7}=2404.475266...$$