Abstract: Objective To investigate factors affecting the determination of the percent carboxyhemoglobin saturation (HbCO%) of blood in an attempt to offer further data for results interpretation and sample storage requirement. Methods The HbCO% of blood samples stored in various conditions were detected by three spec-trophotometries during the succeeding 30 days. Results The data detected by reductive double-wavelength spectrophotometry and double-wavelength spectrophotometry were more stable than mono-wavelength spec-trophotometry. The HbCO% of blood was significantly related with the storage conditions which include temperature,time and the degree of exposure to air. Conclusion Determinations of HbCO% are reliable which performed by reductive double-wavelength spectrophotometry and double-wavelength spectrophotometry,combine with spectral scans. During 30 days,blood stored at 4℃ exposed to a limited volume of air does not influence the determination of HbCO%.

Key words: percent carboxyhemoglobin saturation, spectrophotometry, sample storage condition