The interaction between hemoglobin and two surfactants with different charges.
The interactions of hemoglobin (Hb) with sodium dodecyl sulfate (SDS) and dodecyl trimethylammonium bromide (DTAB) are investigated by several methods. We observed the formation of hemichrome below the critical micelle concentration (cmc) of surfactant and the release of heme from Hb above the cmc. When pH value of Hb/surfactant system is lower than isoelectric point (pI) of Hb, the interaction of SDS with Hb is both electrostatic and hydrophobic, while the interaction of DTAB with Hb is hydrophobic mainly. On the contrary, when pH>pI, the interaction of SDS with Hb is hydrophobic mainly, while the interaction of DTAB with Hb is both electrostatic and hydrophobic. In the case where both the electrostatic interaction and hydrophobic interaction exist, the electrostatic interaction plays a more important role. Thus, SDS tends to interact with Hb more obviously than DTAB does when pH<pI and the interaction between DTAB and Hb is stronger when pH>pI.
Liu
Wenjie
W
School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, PR China.
Guo
Xia
X
Guo
Rong
R
D002151:Calorimetry; D004553:Electric Conductivity; D005614:Freeze Fracturing; D006454:Hemoglobins / Q000737:chemistry*; D007091:Image Processing, Computer-Assisted; D008823:Micelles; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship; D013501:Surface-Active Agents / Q000737:chemistry*
D006454:Hemoglobins; D008823:Micelles; D000644:Quaternary Ammonium Compounds; D013501:Surface-Active Agents; C013912:decyltrimethylammonium; D012967:Sodium Dodecyl Sulfate