Answer:
It depends of the experiment
Explanation:
The measurement of the concentration depends on the way in which the quantification is being carried out.
The first method is based on the law of lamber-beer, A = bce. Where a is the absorbance, b is the optical path and is the molar extension coefficient. All these variables will depend on the method that is being carried out. For example, when you want to measure immunogluboline, you have a molar extinction coefficient of 210,000M-1 cm-1, the optical path is always 1 cm and for this case the absorbance is 1.5, therefore the concentration will be:
[tex]C=\frac{A}{e*b}[/tex]
[tex]C=\frac{1.5}{210000*1}[/tex]
[tex]C=7.4x10^-6 M[/tex]
The second procedure is the calibration curve method. In this case, we have to measure the concentration of several samples and register the absorbance for each sample. In this procedure, we will obtain a lineal formula:
[tex]y=mx+b[/tex]
Where Y is is the absorbance, m is the slope, X is the concentration and b the intercept with the Y-axis. For example, when we messure the concentration of [tex]Cd^+2[/tex] we will have the concentrations (figure 1).
The curve obtained through a linear regression will be:
[tex]y=222.3x-0.0572[/tex]
[tex]Abs=222.3C-0.0572[/tex]
If we replace the value in the equation we will obtain:
[tex]1.5=222.3C-0.0572[/tex]
[tex]C=1482.44 ppm[/tex]
