Three-dimensional polymer networks with channels situated therein
The disclosure provides three-dimensional crosslinked polymer networks comprising one or more channels extending from the surface and/or near the surface of the network into the interior of the network, arrays comprising the networks, processes for making the networks, and uses of the networks and arrays.
1. A three-dimensional network having a surface and an interior, said three-dimensional network:
(a) is composed of a water-swellable polymer of crosslinked water-soluble polymer chains;
(b) is crosslinked to the surface of a substrate;
(c) comprises multiple pluralities of channels, wherein:
(i) each plurality of channels comprises channels that converge at a point in the interior of the network such that the lateral distance between the channels decreases from the surface of the network toward the point in the interior; and
(ii) each plurality of channels converges at a different point in the three-dimensional network; and
(d) comprises probe molecules covalently attached to the polymer chains.
2. The three-dimensional network of claim 1 , wherein a majority of probe molecules are in the interior of the three-dimensional network and/or adjoin a channel.
3. The three-dimensional network of claim 1 , wherein the polymer comprises a polymer polymerized from dimethylacrylamide (DMAA), methacryloyloxybenzophenone (MABP), and sodium 4-vinylbenzenesulfonate (SSNa).
4. An array comprising a plurality of three-dimensional networks according to claim 1 , wherein each of the three-dimensional networks is located at a separate spot on the substrate.
5. The array of claim 4 , which can be reused at least 10 times.
6. A process for making a three-dimensional network, comprising the steps of:
(a) applying a mixture comprising (i) an aqueous salt solution which is optionally a monovalent cation salt solution, (ii) a water-soluble polymer, (iii) a cross-linker, and (iv) probe molecules to a substrate in a volume of 100 pl to 5 nl;
(b) exposing the mixture to needle-shaped crystal forming conditions, thereby forming a mixture containing one or more needle-shaped salt crystals;
(c) exposing the mixture containing the needle-shaped salt crystals to crosslinking conditions, thereby forming a crosslinked polymer network having probe molecules crosslinked thereto and containing needle-shaped salt crystals; and
(d) contacting the crosslinked polymer network containing the needle-shaped salt crystals with a solvent in which the needle-shaped salt crystals are soluble, thereby dissolving the needle-shaped salt crystals and forming channels in place of the needle-shaped salt crystals.
7. The process of claim 6 , wherein:
(a) the solvent is a water-based buffer; and/or;
(b) the needle-shaped crystal salt forming conditions comprise:
(i) dehydrating the mixture; or
(ii) cooling the mixture.
8. A process for making an array, comprising (a) creating a plurality of three-dimensional networks by the process of claim 6 at discrete spots on the surface of the substrate, and (b) crosslinking the plurality of three-dimensional networks to the surface.
9. A method for determining whether an analyte is present in a sample, comprising:
(a) contacting a three-dimensional network according to claim 1 comprising probe molecules that are capable of binding to the analyte with the sample; and
(b) detecting binding of the analyte to the probe molecules in the three-dimensional network, thereby determining whether the analyte is present in the sample and optionally the amount of the analyte.
10. The method of claim 9 , wherein the three-dimensional network has been used and washed at least 10 times prior to (a) or which further comprises reusing the three-dimensional network at least 10 times following (b).
11. The method of claim 10 , which further comprises quantifying binding of the analyte to the probe molecules in the three-dimensional network.
12. The three-dimensional network of claim 1 , wherein the three-dimensional network comprises two to ten pluralities of channels, each plurality converging at a different point within the three-dimensional network.
13. The three-dimensional network of claim 1 , wherein the three-dimensional network comprises two pluralities of channels, each plurality converging at a different point within the three-dimensional network.
14. The three-dimensional network of claim 1 , wherein the probe molecules comprise nucleic acids.
15. The three-dimensional network of claim 14 , wherein the nucleic acids are oligonucleotides.
16. The array of claim 4 , wherein the plurality of three-dimensional networks comprises two or more three-dimensional networks comprising different species of probe molecules.
17. The array of claim 4 , wherein the plurality of three-dimensional networks comprises one or more three-dimensional networks comprising labeled control probe molecules.
18. The array of claim 17 , wherein the labeled control probe molecules are fluorescently labeled.
19. The array of claim 17 , wherein at least one control probe molecule is a spatial control probe.
20. The array of claim 17 , wherein at least one control probe molecule is a reusability control probe.
21. The array of claim 20 , wherein the reusability control probe is also a spatial control probe.