Electrocasting - formation and structuring of suspended microbodies using a.c. generated field cages

Hybrid microelectrode chip structures were used to generate three dimensional field cages. The a.c. field generated negative dielectrophoretic forces and caused suspended particles to aggregate. The shape and size of the aggregate depends on the material, suspending liquid, electrode arrangement, electrode driven and size. Particle-aggregates can be stabilised by chemical or physical means. Photopolymerization was used to solidify latexes into artificial microbodies in the micrometer range and antibody-mediated agglutination was also used. Single particles or aggregates can be covered by one or more layers of different materials and geometries. We show a glass sphere covered by a structured multivesicular coating and a gas bubble covered by a latex particle layer.The microbody casting technology can find application in materials science, pharmaceutical formulation and biotechnology.

[1]  A. Andrews.  Electrophoresis: Theory, Techniques, and Biochemical and Clinical Applications , 1981 .

[2]  Eppstein Da,et al.  Alternative delivery systems for peptides and proteins as drugs. , 1988 .

[3]  R. Jalil,et al.  Biodegradable poly(lactic acid) and poly(lactide-co-glycolide) microcapsules: problems associated with preparative techniques and release properties. , 1990, Journal of microencapsulation.

[4]  R. Bodmeier,et al.  Drug release from laminated polymeric films prepared from aqueous latexes. , 1990, Journal of pharmaceutical sciences.

[5]  G. Rafler,et al.  Parenterale Depotarzneiformen auf der Basis von biologisch abbaubaren Polymeren , 1991 .

[6]  B Wagner,et al.  Levitation, holding, and rotation of cells within traps made by high-frequency fields. , 1992, Biochimica et biophysica acta.

[7]  H. Kohlmann,et al.  E-beam induced fabrication of microstructures , 1992, [1992] Proceedings IEEE Micro Electro Mechanical Systems.

[8]  M. Boman,et al.  Helical microstructures grown by laser assisted chemical vapor deposition , 1992, [1992] Proceedings IEEE Micro Electro Mechanical Systems.

[9]  Klaus Mosbach,et al.  Drug assay using antibody mimics made by molecular imprinting , 1993, Nature.

[10]  G. Fuhr,et al.  Three-dimensional electric field traps for manipulation of cells--calculation and experimental verification. , 1993, Biochimica et biophysica acta.

[11]  N. Nakajima,et al.  Photoforming applied to fine machining , 1993, [1993] Proceedings IEEE Micro Electro Mechanical Systems.

[12]  K. Ikuta,et al.  Real three dimensional micro fabrication using stereo lithography and metal molding , 1993, [1993] Proceedings IEEE Micro Electro Mechanical Systems.

[13]  Reinhard Miller,et al.  Surface chemical characterization of maleic-acid mono[2-(4- alkylpiperazinyl)ethyl esters]. 2. pH-dependent adsorption behavior of an ampholytic surfactant , 1994 .

[14]  E Tamiya,et al.  Multisample analysis using an array of microreactors for an alternating-current field-enhanced latex immunoassay. , 1994, Analytical chemistry.

[15]  F. Becker,et al.  A unified theory of dielectrophoresis and travelling wave dielectrophoresis , 1994 .

[16]  G. Fuhr,et al.  Cell manipulation and cultivation under a.c. electric field influence in highly conductive culture media. , 1994, Biochimica et biophysica acta.