My book NCERT(Class 12, Surface chemistry) claims that hemoglobin is a positively charged sol.
The cytosolic pH in human cells is around 7.4, but fluctuates through the cell cycle
according to this article the isoelectric point of Hemoglobin behaves as follows:
The more nearly free a preparation of hemoglobin is from nonhemoglobin protein the more nearly does the isoelectric point approach 6.8,
So if the isoelectric point is 6.8 for Hemoglobin and pH of cytoplasm is 7.4 so wouldn't be Hemoglobin a negatively charged sol?
As we know in blood, proteins exist as negatively charged species so blood is termed as negatively charged sol, so is there a point I am missing?