Diffusion and partitioning of macromolecules within finely porous glass

Abstract

Measurements of diffusion and partitioning of nearly monodisperse polystyrene, having molecular weights of from 600 to 670,000, in chloro‐form and dichloroethane and of two proteins in aqueous solution were made with leached borosilicate glass cubes having a narrow pore size distribution and pore radi of from 2.5 to 47.6 nm. With increasing ratio of molecular to pore size, the partition coefficient for all solutes decreased; the ratio of effective to bulk diffusivity decreased for the proteins but remained constant for polystyrene. This suggests that polystyrene behaved like a free‐draining macromolecule under the conditions of this study.

DNA confined in nanochannels: Hairpin tightening by entropic depletion

“…[1][2][3][4][5][6][7][8] Recent advances in chip lithography have led to the fabrication of well-defined nanochannels 9,10 so that issues in polymer physics may now be addressed which were elusive in the past. [11][12][13][14][15][16][17][18][19] At the same time, stiff polymers such as DNA and actin can now be well aligned which is of considerable interest in the biosciences.…”

Configurational diffusion of asphaltenes in fresh and aged catalyst extrudates. Final technical report, September 20, 1991--September 30, 1996

“…Some other results conflicting with hindered diffusion theory have also been observed in the diffusion of polystyrenes with porous glasses (Colton et al, 1975;Giddings et al, 1977;Kline and Griineberg, 198l), which showed significantly lower and essentially constant effective diffusivities. For example, Colton et al (1975) studied the diffusion of polystyrenes of molecular weight from 600 to 670000 in leached borosilicate glass cubes of 2.5 to 47.6 nm pore sizes and found that the ratio of effective to bulk diffusivities was constant for different polystyrene sizes.…”

“…For example, Colton et al (1975) studied the diffusion of polystyrenes of molecular weight from 600 to 670000 in leached borosilicate glass cubes of 2.5 to 47.6 nm pore sizes and found that the ratio of effective to bulk diffusivities was constant for different polystyrene sizes. They suggested that the random coiling polystyrenes behaved like free-draining macromolecules, and for restricted diffusion the effective size scale of the polymer was comparable to that of the monomer unit.…”

“…Several investigators have used different methods to estimate the molecular size of polystyrene in hindered diffusion studies. Colton et al (1975) suggested that the size of the monomer unit, instead of the randomly coiled polymer, might be used in fitting hindered diffusion data. More recent studies by Bishop et al (1989) and Dimino (1994) indicated that a hard sphere model for the randomly coiled polystyrene gave good agreement of experimental data with the hindered diffusion theory.…”

Hindered diffusion of coal liquids. Quarterly report No. 12, June 18, 1995--September 17, 1995

“…Colton et aZ. [24] studied diffusion of proteins and polystyrene in porous glass and found that protein diffusion follows Renkin's theory, while polystyrene behaves as a free draining molecule. Cannel and Rondelez [25] measured diffusion of polystyrene through a Nuclepore membrane and found that polystyrene diffusion follows Renkin's theory, if X is corrected by a factor of 1.45.…”