OBSERVATIONS ON ANOMALOUS RETENTION IN STERIC FIELD-FLOW FRACTIONATION

被引:139
作者
CALDWELL, KD
NGUYEN, TT
MYERS, MN
GIDDINGS, JC
机构
[1] Department of Chemistry, University of Utah, Salt Lake City
基金
美国国家卫生研究院;
关键词
D O I
10.1080/01496397908058103
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
We discuss two anomalies that have characterized our recent work in steric field-flow fractionation (steric FFF): (a) retention has been found to vary with flow rate, contrary to simple theory; and (b) low density cells elute earlier than theory predicts. After reviewing the theory, we describe experiments in both gravitational and centrifugal fields applied to two spherical beads (microporous silica and polystyrene latex) of essentially equal sizes but different densities. The velocity dependence of retention is verified for both kinds of particles, but we find that retention depends dramatically on density as well. We speculate that these anomalous dependencies originate in a velocity-dependent lift force acting to pull the particle away from the wall. This hypothesis is supported by the observation that an increase in field strength increases retention. We conclude that a controllable field strength (as in a centrifuge) is an important asset in steric FFF, permitting increased separation speed and allowing the option of separating particles on the basis of density as well as size. © 1979, Taylor & Francis Group, LLC. All rights reserved.
引用
收藏
页码:935 / 946
页数:12
相关论文
共 8 条
[2]   FLOW PROGRAMMED FIELD-FLOW FRACTIONATION [J].
GIDDINGS, JC ;
CALDWELL, KD ;
MOELLMER, JF ;
DICKINSON, TH ;
MYERS, MN ;
MARTIN, M .
ANALYTICAL CHEMISTRY, 1979, 51 (01) :30-33
[3]   STERIC FIELD-FLOW FRACTIONATION - NEW METHOD FOR SEPARATING 1-MU-M TO 100-MU-M PARTICLES [J].
GIDDINGS, JC ;
MYERS, MN .
SEPARATION SCIENCE AND TECHNOLOGY, 1978, 13 (08) :637-645
[4]  
GIDDINGS JC, METHODS BIOCH ANAL
[5]  
GIDDINGS JC, UNPUBLISHED
[6]  
GIDDINGS JC, 1976, COLLOID INTERFACE SC, V4
[7]   CONTINUOUS STERIC FFF DEVICE FOR THE SIZE SEPARATION OF PARTICLES [J].
MYERS, MN ;
GIDDINGS, JC .
POWDER TECHNOLOGY, 1979, 23 (01) :15-20
[8]   LIFT ON A SMALL SPHERE IN A SLOW SHEAR FLOW [J].
SAFFMAN, PG .
JOURNAL OF FLUID MECHANICS, 1965, 22 :385-&