Method of making random array of microspheres using enzyme digestion
View Patent ↗A method of making a microarray comprising the steps of:—providing a support;—coating on the support a fluid composition containing microspheres and gelatin;—immobilizing the microspheres in the gelatin coating;—partially digesting the gelatin with an enzyme to expose surfaces of the microspheres; and—removing the enzyme and digested gelatin from the coating.
1. A method of making a microarray comprising the steps of:
providing a support;
coating on at least one surface of the support a fluid composition containing microspheres and gelatin;
immobilizing the microspheres in the gelatin coating;
partially digesting the gelatin with an enzyme to expose surfaces of the microspheres; and
removing the enzyme and digested gelatin from the coating, such that a first portion of the microspheres is submerged in the gelatin coating on the support and a second portion is exposed above the gelatin coating and is substantially free of gelatin.
2. The method according to claim 1 wherein the composition is coated on the support using machine coating.
3. The method according to claim 1 wherein the immobilization of the microspheres is preserved upon gelation of the gelatin.
4. A method according to claim 3 wherein the coating composition undergoes rapid gelation by chill setting immediately after coating.
5. A method according to claim 1 wherein the enzyme is esperase, alcalase, savinase, or papain.
6. A method according to claim 1 wherein enzyme digestion is terminated by immersing the support with the gelatin coating into a solution that contains no enzyme.
7. A method according to claim 6 wherein the solution that contains no enzyme is an aqueous solution.
8. A method according to claim 1 wherein the exposed surfaces of the microspheres bear nucleic acid probes.
9. A method according to claim 8 wherein the nucleic acid probes on the surfaces of the microspheres are oligonucleotides, DNA, DNA fragments, PNAs, or synthetic molecules capable of interacting specifically with a nucleic acid sequence.
10. A microarray comprising: a support having at least one surface containing microspheres immobilized in a gelatin coating; wherein a first portion of the microspheres is submerged in the gelatin coating and a second portion is exposed above the gelatin coating and is substantially free of gelatin.
11. A microarray according to claim 10 wherein the immobilization of the microspheres on the gelatin coating is preserved upon gelation of the gelling agent.
12. A microarray according to claim 10 wherein the microspheres bear chemically active sites.
13. A microarray according to claim 12 wherein the chemically active sites comprise nucleic acid.
14. A microarray according to claim 10 wherein the support comprises glass, plastic, cellulose acetate, or polyethyleneterephthalate.
15. A microarray according to claim 10 wherein the support is flexible.
16. A method of making a microarray comprising the steps of:
providing a support;
coating on at least one surface of the support a fluid composition containing microspheres and gelatin; and
immobilizing the microspheres on the support by allowing gelation of the gelatin such that a first portion of the microspheres is submerged in the gelatin and a second portion is exposed above the gelatin and is substantially free of gelatin; wherein the support has no predetermined sites to attract the microspheres.
17. A method according to claim 16 wherein the composition is coated on the support using knife coating, blade coating or slot coating.
18. A method according to claim 1 or 16 wherein the composition is fluid during coating and the microspheres become randomly immobilized on the support in the plane of coating upon gelation of the gelatin.