Polymeric nanopillars and nanotubes, their manufacture and uses

Patent metadata

Field	Value
Publication number	US-9718676-B2
Application number	US-44054607-A
Country	US
Kind code	B2
Filing date	Sep 12, 2007
Priority date	Sep 14, 2006
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

A method is disclosed for fabricating free-standing polymeric nanopillars or nanotubes with remarkably high aspect ratios. The nanopillars and nanotubes may be used, for example, in integrated microfluidic systems for rapid, automated, high-capacity analysis or separation of complex protein mixtures or their enzyme digest products. One embodiment, preferably fabricated entirely from polymer substrates, comprises a cell lysis unit; a solid-phase extraction unit with free-standing, polymeric nanostructures; a multi-dimensional electrophoretic separation unit with high peak capacity; a solid-phase nanoreactor for the proteolytic digestion of isolated proteins; and a chromatographic unit for the separation of peptide fragments from the digestion of proteins. The nanopillars and nanotubes may also be used to increase surface area for reaction with a solid phase, for example, with immobilized enzymes or other catalysts within a microchannel, or as a solid support for capillary electrochromatography-based separations of proteins or peptides.

First claim

What is claimed:

1. An integrated system for analysis of proteins and mixtures of proteins, wherein said system is contained on a single, monolithic microchip, said system comprising:
(a) an input adapted to receive a sample and to deliver it to a solid-phase protein extractor;
(b) a solid-phase protein extractor adapted to extract and concentrate proteins from the sample, and to output the extracted proteins to a first separation channel;
(c) a first separation channel having a diameter less than about 100 μm, whose surface is adapted to separate the proteins by a first characteristic, wherein said first separation channel is adapted to output the separated proteins to a second separation channel;
(d) a second separation channel having a diameter less than about 100 μm, whose surface is adapted to separate the proteins by a second characteristic, wherein said second separation channel is adapted to output the separated proteins to a solid-phase enzymatic reactor; wherein the first and second separation characteristics are substantially different;
(e) a flow-through, solid-phase enzymatic reactor whose surface comprises one or more covalently-bound enzymes adapted to at least partially digest the separated proteins, and to output the digested proteins to a peptide separator; and
(f) a peptide separator adapted to separate the peptide protein digest products by a third characteristic, wherein the third characteristic may be the same as the first or second characteristic, or different from both; and wherein said peptide separator is adapted to output the separated peptides to a detector;

wherein:
(g) each of said solid-phase extractor, said enzymatic reactor, said first separation channel, and said second separation channel comprises an array of nanopillars having diameters between about 60 nm and about 500 nm, and aspect ratios 500 or higher, wherein said nanopillars comprise a synthetic polymer; wherein said nanopillars have solid interiors; and wherein said nanopillars are not hollow;

and wherein:
(h) each said array of nanopillars is prepared by a process comprising the steps of:
(i) supplying a template of anodic aluminum oxide, wherein at least one surface of the template has a shape complementary to the shape of at least one surface of the nanopillars to be made;
(ii) impregnating at least the complementary surface of the template with a liquid comprising a solution of a polymer, or comprising a solution of a monomer precursor of a polymer, or comprising a polymer melt;
(iii) forming a solid polymer structure in the impregnated template by cooling the liquid or by inducing polymerization of monomer precursors in the liquid;
(iv) removing the template from the solid polymer structure; and
(v) avoiding or reducing surface-tension-induced damage to the solid polymer structure by keeping it immersed in a liquid, or by removing residual liquid by freeze-drying, or by removing residual liquid by supercritical drying;
wherein:
(vi) the solid polymer structure that is produced comprises one or more arrays of intact nanopillars, wherein the nanopillars have diameters between about 60 nm and about 500 nm, and an aspect ratio that is 500 or higher.

2. The integrated system of claim 1 , wherein the liquid comprises a solution of a polymer or a solution of a monomer precursor of a polymer, wherein the surface tension of the liquid causes the liquid to adhere to the surface of pores in the template, and whose viscosity is such that the interior of the pores fills, whereby the nanopillars formed comprise nanopillars with solid interiors.

3. The integrated system of claim 1 , wherein the nanopillars have an aspect ratio that is at least about 1000.

4. The integrated system of claim 1 , wherein the nanopillars have an aspect ratio that is at least about 1600.

5. The integrated system of claim 1 , wherein said sample-receiving input additionally comprises a cell-lysis unit, a cell-selection unit, or both.

6. The integrated system of claim 1 , wherein the surfaces of at least some of said nanopillars are chemically functionalized.

7. The integrated system of claim 1 , wherein one or more of the first, second, and third characteristics is selected from the group consisting of microcapillary gel electrophoresis and micellar electrokinetic chromatography.

8. The integrated system of claim 1 , wherein each of the first, second, and third characteristics is selected from the group consisting of microcapillary gel electrophoresis, and micellar electrokinetic chromatography.

Assignees

• Soper Steven A
• Mccarley Robin L
• Chen Guofang
• Shadpour Hamed
• Univ Louisiana State

Inventors

• Soper Steven A
• Mccarley Robin L
• Chen Guofang
• Shadpour Hamed

Classifications

• B81C2201/034

  Moulding · CPC title

• G01N27/44773

  Multi-stage electrophoresis, e.g. two-dimensional electrophoresis · CPC title

• Y10T428/2982

  Particulate matter [e.g., sphere, flake, etc.] · CPC title

• B81C1/00111 Primary

  Tips, pillars, i.e. raised structures (microneedles A61M37/0015) · CPC title