稀溶液中Laponite与胶原的相互作用及其分散稳定性

Interaction between Laponite and Collagen in Dilute Solutions and Effect on Dispersion Stability

首先研究了形成稳定合成锂藻土Laponite-胶原分散液的条件,然后通过紫外和Zeta电位测试研究了Laponite与胶原的相互作用以及分散液的稳定性。结果表明:胶原和Laponite的浓度以及溶液的pH都会影响分散液的稳定性;UV测试表明Laponite与胶原之间是非共价相互作用。当胶原浓度增大时,肽链有聚集趋势而使分散液稳定性降低。随着Laponite在胶原溶液中含量的增加,Zeta电位先升高再降低,说明稀溶液中胶原分子链与Laponite表面之间的静电作用,决定了分散体系的稳定性。尽管单独的Laponite在高pH溶液环境更为稳定,但Laponite-胶原分散体系在低pH值时的Zeta电位值较高,稳定性较好。

The formation conditions of stable Laponite - collagen dispersions were studied firstly. Then UV and Zeta potential tests were performed to explore the interaction of Laponite - collagen and the stability of the dispersion. The results indicate that collagen concentration, Laponite dosage and pH have influence on the stability of Laponite - collagen dispersion. UV spectra show that the non - covalent interaction occurs between Laponite and collagen in dilute solutions. Collagen chains tend to aggregate and the stability decreases with the increase of the collagen concentration. Increasing the content of Laponite in the collagen solution leads to the increase of Zeta potential at first and then decrease in the presence of more Laponite, showing that electrostatic interactions between the negative charged surface of Laponite and the positive charged groups of collagen chains dominate the stability of Laponite - collagen dispersion. Although Laponite is more stable in higher pH solutions, the dispersion shows more stable under lower pH conditions.