Two-dimensional colloidal crystals formed by thermophoresis and convection

被引：95

作者：

Duhr, S ^{[1
]}

Braun, D ^{[1
]}

机构：

[1] Univ Munich, Dissipat Biosyst Lab, D-80799 Munich, Germany

来源：

APPLIED PHYSICS LETTERS | 2005年 / 86卷 / 13期

关键词：

D O I：

10.1063/1.1888036

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Temperature gradients can trap micrometer-sized particles into two-dimensional crystals. We form colloidal crystals from otherwise repellent 2 mu m polystyrene beads in diverse thermal convection settings. Our experiments indicate that the accumulation is driven by particle thermophoresis. Particles move along the temperature gradient and are pushed out of the warm liquid to a cold wall. We find reduced accumulation for decreased surface temperature gradients and enhanced salt concentrations. Moreover, thermophoretic fluid dynamics calculations predict flat accumulation profiles with 10(7)-fold enhanced concentrations that are consistent with our experiments. The accumulated crystals could be used as molecular sieves for microfluidic biotechnological applications. A natural environment for similar accumulations are pores of rock near hydrothermal vents. (C) 2005 American Institute of Physics.

引用

页码：1 / 3

页数：3

共 31 条

[1] NUCLEATION AND GROWTH OF COLLOIDAL CRYSTALS [J].

AASTUEN, DJW ;

CLARK, NA ;

COTTER, LK ;

ACKERSON, BJ .

PHYSICAL REVIEW LETTERS, 1986, 57 (14) :1733-1736

[2]

[Anonymous], 1969, NONEQUILIBRIUM THERM

[3] Thermal force approach to molecular evolution [J].

Braun, D ;

Libchaber, A .

PHYSICAL BIOLOGY, 2004, 1 (1-2) :P1-P8

[4] Trapping of DNA by thermophoretic depletion and convection [J].

Braun, D ;

Libchaber, A .

PHYSICAL REVIEW LETTERS, 2002, 89 (18) :1-188103

[5] CHARACTERIZATION OF OPTICAL DIFFRACTION AND CRYSTAL-STRUCTURE IN MONODISPERSE POLYSTYRENE COLLOIDS [J].

CARLSON, RJ ;

ASHER, SA .

APPLIED SPECTROSCOPY, 1984, 38 (03) :297-304

[6] SINGLE COLLOIDAL CRYSTALS [J].

CLARK, NA ;

HURD, AJ ;

ACKERSON, BJ .

NATURE, 1979, 281 (5726) :57-60

[7]

Clusis K, 1939, Z PHYS CHEM B-CHEM E, V44, P397

[8] Molecular origin of thermal diffusion in benzene plus cyclohexane mixtures -: art. no. 055901 [J].

Debuschewitz, C ;

Köhler, W .

PHYSICAL REVIEW LETTERS, 2001, 87 (05) :55901-1

[9] Thermophoresis of DNA determined by microfluidic fluorescence [J].

Duhr, S ;

Arduini, S ;

Braun, D .

EUROPEAN PHYSICAL JOURNAL E, 2004, 15 (03) :277-286

[10] A microfabricated thermal field-flow fractionation system [J].

Edwards, TL ;

Gale, BK ;

Frazier, AB .

ANALYTICAL CHEMISTRY, 2002, 74 (06) :1211-1216

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