Class: BE210
Group: W5
Members: FACILITATOR Naomi Sta. Maria,  TIME & TASK KEEPER Jeffrey P. Wu, SCRIBE Matthew Fink, PRESENTER Anju Mathew
Date: 5/11/00
Full Text

Abstract:

The wavelengths and molar extinction coefficients at isosbestic points and peaks of oxy and deoxy hemoglobin were precisely determined.  Wavelengths were determined to within less than 0.1% uncertainty and extinction coefficients were determined to within less than 2.0% uncertainty.  Three isosbestic points were found in the range of 500-600 nm.  At wavelengths of 546.8 ? 0.2 nm, 570.8 ? 0.2 nm, and 586.1 ? 0.2 nm, the molar extinction coefficients are 34190 ? 690 L/mol-cm, 30910 ? 220 L/mol-cm, and 24040 ? 120 L/mol-cm, respectively.  Two peaks were found for oxy hemoglobin and one for deoxy hemoglobin.  They are located at 540.5 ? 0.3 nm and 575.8 ? 0.3 nm for oxy hemoglobin and at 554.7 ? 0.3 nm for deoxy.  The corresponding molar extinction coefficients are 35550 ? 360 L/mol-cm and 32840 ? 450 L/mol-cm for the oxy peaks and 35310 ? 150 L/mol-cm for the deoxy peak.  The limiting amount of sodium dithionite necessary to reduce oxy hemoglobin to deoxy hemoglobin is 9.763 mg/mg oxy hemoglobin with an uncertainty of ? 1.255 mg/mg oxy hemoglobin.  Testing of the procedure to determine concentration ratios of oxy/deoxy in a mixture yielded a theoretical ratio of 1:1 using one-half the limiting amount of sodium dithionite.  Experimental procedure yielded a concentration ratio of 1:104, which is equivalent to a 10,300% error.