Direct labeling: | Light (16O2) | Mixed (16O, 18O) | Heavy (18O2) |
---|
Treated (Lab. pep.): |
|
|
|
Control (Unlab. pep.): |
| | |
Intensities: I
D
|
a
D
|
b
D
|
c
D
|
Inverted labeling:
| Light (16O2) | Mixed (16O, 18O) | Heavy (18O2) |
Control (Lab. pep.): |
|
|
|
Treated (Unlab. pep.): |
| | |
Intensities: I
I
|
a
I
|
b
I
|
c
I
|
- The theoretical quantities used to derive the ratio between treated and control samples are listed. The desired intensities for treated and control samples were calculated from the estimated intensities (see Eq. 2II–III) resulting from the multivariate linear regression fit after normalization (a, b and c). The total intensity of a spectra I = a + b + c, where in the table subscripts D and I are added referring to the Direct and Inverted experiments, respectively, and the superscripts T and C are added referring to treated and control samples, respectively.