### Tabulated Molar Extinction Coefficient for Hemoglobin in Water

These values for the molar extinction coefficient e in [cm-1/(moles/liter)] were compiled by Scott Prahl (scott.prahl@oit.edu) using data from

• J.M. Schmitt, "Optical Measurement of Blood Oxygenation by Implantable Telemetry," Technical Report G558-15, Stanford."
• M.K. Moaveni, "A Multiple Scattering Field Theory Applied to Whole Blood," Ph.D. dissertation, Dept. of Electrical Engineering, University of Washington, 1970.

To convert this data to absorbance A, multiply by the molar concentration and the pathlength. For example, if x is the number of grams per liter and a 1 cm cuvette is being used, then the absorbance is given by

```        (e) [(1/cm)/(moles/liter)] (x) [g/liter] (1) [cm]
A =  ---------------------------------------------------
66,500 [g/mole]
```
using 66,500 as the gram molecular weight of hemoglobin.

To convert this data to absorption coefficient in (cm-1), multiply by the molar concentration and 2.303,

µa = (2.303) e (x g/liter)/(66,500 g Hb/mole)
where x is the number of grams per liter. A typical value of x for whole blood is x=150 g Hb/liter.
```lambda	HbO2	Hb
nm	cm-1/M	cm-1/M
630	680	4280
640	440	3640
650	380	3420
660	320	3200
670	320	3080
680	320	2960
690	280	2560
700	320	2160
710	340	1840
720	360	1520
730	400	1500
740	440	1520
750	520	1620
760	600	1720
770	660	1420
780	720	1120
790	760	1020
800	800	920
810	860	880
820	920	840
830	980	840
840	1040	840
850	1060	800
860	1080	840
870	1120	840
880	1160	840
890	1180	860
900	1200	880
910	1220	920
920	1240	880
930	1240	800
940	1200	800
950	1200	720
```