Suh Chang Woo, Kim Min Young, Choo Jae Bum, Kim Jong Kil, Kim Ho Kun, Lee Eun Kyu
Bioprocessing Research Laboratory, Department of Chemical Engineering, Hanyang University, Ansan 425-791, South Korea.
J Biotechnol. 2004 Sep 9;112(3):267-77. doi: 10.1016/j.jbiotec.2004.05.005.
The effect of average pore size of nano-pore silica particles on protein adsorption characteristics was determined experimentally by the dissociation constant and the adsorption capacity determined from the Langmuir equation. As the average pore size was increased from 2.2 to 45 nm, the BSA adsorption capacity increased from 16.8 to 84.3 mg/g-silica so as the equilibrium constant (from 2.6 to 9.4 mg/ml). Using confocal microscopy with fluorescence labeling, we could visualize the protein adsorption in situ and determine the minimum pore size required for efficient intraparticle adsorption. The confocal microscopy analysis revealed that BSA was adsorbed mainly on the surface of the particles with a smaller pore size, but diffused further into the interstitial surface when it was sufficiently large. It was concluded that for BSA whose Stoke's diameter is ca. 3.55 nm the minimum pore size of about 45 nm or larger was required for a sufficient adsorption capacity.
通过解离常数和由朗缪尔方程确定的吸附容量，实验测定了纳米孔二氧化硅颗粒的平均孔径对蛋白质吸附特性的影响。随着平均孔径从2.2纳米增加到45纳米，牛血清白蛋白（BSA）的吸附容量从16.8毫克/克-二氧化硅增加到84.3毫克/克-二氧化硅，平衡常数也随之增加（从2.6毫克/毫升增加到9.4毫克/毫升）。使用荧光标记的共聚焦显微镜，我们可以原位观察蛋白质吸附情况，并确定颗粒内有效吸附所需的最小孔径。共聚焦显微镜分析表明，BSA主要吸附在孔径较小的颗粒表面，但当孔径足够大时，会进一步扩散到颗粒间表面。得出的结论是，对于斯托克斯直径约为3.55纳米的BSA，要获得足够的吸附容量，所需的最小孔径约为45纳米或更大。
