The Use of Zeta Potential Measurement for Determining Isoelectric Points of Collagen and its Degradations

Zeta potential measurement was used for determining isoelectric points of collagen and its degradations.The determination results were compared with those of isoelectrofocusing determinations.Several factors,such as concentration,temperature,were studied.The results showed that isoelectric point values which determined by Zeta potential method were coincident with that of isoelectric focusing determinations,so this method could be used to determine the isoelectric point of collagen and its degradations.When the determination temperature increased between 25 ℃and 40 ℃,the results would shift to higher pH value,but the difference of the results were less than 0.1 pH.The concentration of collagen and its degradations should be controlled in 0.2-0.5mg/mL for this method,even which was less than 0.1 mg/mL also could maintain good determination results.