Fluidization characteristics of and protein adsorption on fluoride-modified porous zirconium oxide particles.
Fluidization characteristics of and protein adsorption on fluoride-modified porous zirconium oxide particles.
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DOI：
10.1016/s0021-9673(97)00282-3
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发表时间：
1997-08
期刊：
影响因子：
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通讯作者：
C. M. Griffith;J. Morris;M. Robichaud;M. Annen;A. McCormick;M. Flickinger
中科院分区：
文献类型：
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作者：
C. M. Griffith;J. Morris;M. Robichaud;M. Annen;A. McCormick;M. Flickinger
采用油乳液法从1000 μ l胶体中合成了比重为3.2 g/ml、平均粒径为50 μm、在水中的终沉速度为2.8 mm/s的多孔氧化锆颗粒，并对其在膨胀床蛋白质吸附中的潜在应用进行了评价。即使对于小体积、浅床（沉降床：10 ml，高径比<1.0），甚至对于大得多的颗粒所共有的流化速度（对于三倍床膨胀为210 cm/h），颗粒的膨胀床也是稳定的。当这些颗粒的表面被氟吸附改性时，在109-210 cm/h的线速度下，对牛血清白蛋白（BSA）的总床容量为42±2 mg BSA/ml的沉降床体积。在非约束条件下的几种溶质的停留时间分布的研究进行了评估的程度的液体混合和沟流在膨胀床作为流化速度的函数。还研究了液体混合和沟流作为分布器设计的函数。对于这些非常致密的颗粒，沟道和混合的程度不会随着膨胀程度而恶化。洗脱吸附的BSA，而床被扩大（通过一步增加离子强度）是快速的，导致在高流化速度下的窄峰，而不诉诸于沉降的床。5%穿透时BSA的动态结合能力（蛋白流出物浓度等于入口浓度的5%）对于两倍膨胀床与沉降床相同（22±2 mg BSA/ml沉降床体积），尽管其对于较高的床膨胀有所降低。BSA结合是可重复的吸附剂用0.25 M氢氧化钠反复清洗后。
Porous zirconia particles of specific gravity ∼3.2 g/ml, mean particle sizes of ∼50 μm, and terminal settling velocity of ∼2.8 mm/s in water, were synthesized using an oil emulsion method from 1000 Å colloids and were evaluated for their potential use in expanded bed protein adsorption. Expanded beds of particles were stable even for small volume, shallow beds (settled bed: 10 ml, height to diameter ratio <1.0) and even for fluidization velocities common to much larger particles (210 cm/h for a three-fold bed expansion). When the surface of these particles was modified by fluoride adsorption, the total bed capacity for bovine serum albumin (BSA) adsorption was 42±2 mg BSA/ml of settled bed volume at linear velocities of 109–210 cm/h. Residence time distribution studies of several solutes under non-binding conditions were performed to assess the degree of liquid mixing and channeling in the expanded bed as a function of fluidization velocity. Liquid mixing and channeling were also studied as a function of distributor design. With these very dense particles, the degree of channeling and mixing did not worsen with the degree of expansion. Elution of adsorbed BSA while the bed was expanded (by a step increase in ionic strength) was rapid resulting in a narrow peak at high fluidization velocities without resorting to settling of the bed. The dynamic binding capacity of BSA at 5% breakthrough (protein effluent concentration equal to 5% of the inlet concentration) was the same for a two-fold expanded bed as for a settled bed (22±2 mg BSA/ml of settled bed volume), though it decreased for higher bed expansions. BSA binding was reproducible following repeated cleaning of the adsorbent with 0.25 M sodium hydroxide.