Polymer coatings

A method of preparing an array of polynucleotides, said method comprising:

• providing a substrate having a polymer coating present on a surface of the substrate, the polymer coating comprising a recurring unit of Formula (Ia) and a recurring unit of Formula (II):
• wherein:
• R1 is selected from hydrogen, halo, alkyl, alkoxy, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, heterocyclyl, or optionally substituted variants thereof;
• RA is selected from the group consisting of amine, optionally substituted alkene, optionally substituted alkyne, oxo-amine, azido, formyl, hydroxy, hydrazinyl, hydrazonyl, cyanuric chloride, thiocyanate, carboxylic acid, glycidyl, activated ester, epoxy, aziridine, triazoline, and thiol;
• each R4, R4′, R5 and R5′ is independently selected from H, R6, OR6, —C(O)OR6, —C(O)R6, —OC(O)R6, —C(O) NR7R8, or —NR7R8;
• R6 is independently selected from H, OH, alkyl, cycloalkyl, hydroxyalkyl, aryl, heteroaryl, heterocyclyl, or optionally substituted variants thereof;
• each R7 and R8 is independently selected from H or alkyl, or R7 and R8 are joined together with the atom or atoms to which they are attached to form a heterocycle;
• each of the —(CH2)—0 can be optionally substituted;
• o is an integer between 1-50;
• and
• reacting a plurality of first oligonucleotides with reactive sites of the polymer coating to produce a plurality of first oligonucleotides attached to the polymer coating.

A flow cell comprising a substrate, said substrate having a surface comprising a polymer coating covalently attached thereto, wherein the polymer coating comprises a recurring unit of Formula (Ia) and a recurring unit of Formula (II):

• wherein:
• R1 is selected from hydrogen, halo, alkyl, alkoxy, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, heterocyclyl, or optionally substituted variants thereof;
• RA is selected from the group consisting of amine, optionally substituted alkene, optionally substituted alkyne, oxo-amine, azido, formyl, hydroxy, hydrazinyl, hydrazonyl, cyanuric chloride, thiocyanate, carboxylic acid, glycidyl, activated ester, epoxy, aziridine, triazoline, and thiol;
• each R4, R4′, R5 and R5′ is independently selected from H, R6, OR6, —C(O)OR6, —C(O)R6, —OC(O)R6, —C(O) NR7R8, or —NR7R8;
• R6 is independently selected from H, OH, alkyl, cycloalkyl, hydroxyalkyl, aryl, heteroaryl, heterocyclyl, or optionally substituted variants thereof;
• each R7 and R8 is independently selected from H or alkyl, or R7 and R8 are joined together with the atom or atoms to which they are attached to form a heterocycle;
• each of the —(CH2)—o can be optionally substituted;
• and
• o is an integer between 1-50.

A method of determining a nucleotide sequence of a polynucleotide, said method comprising the steps of:

• (a) contacting a polynucleotide polymerase with polynucleotide clusters attached to a surface of a substrate via a polymer coating present on the surface of the substrate;
• wherein the polymer coating comprises a recurring unit of Formula (Ia) and a recurring unit of Formula (II):
• wherein:
• R1 is selected from hydrogen, halo, alkyl, alkoxy, alkenyl, alkynyl, cycloalkyl, aryl, heteroaryl, heterocyclyl, or optionally substituted variants thereof;
• RA is selected from the group consisting of amine, optionally substituted alkene, optionally substituted alkyne, oxo-amine, azido, formyl, hydroxy, hydrazinyl, hydrazonyl, cyanuric chloride, thiocyanate, carboxylic acid, glycidyl, activated ester, epoxy, aziridine, triazoline, and thiol;
• each R4, R4′, R5 and R5 ′ is independently selected from H, R6, OR6, —C(O)OR6, —C(O)R6, —OC(O)R6, —C(O) NR7R8, or —NR7R8;
• R6 is independently selected from H, OH, alkyl, cycloalkyl, hydroxyalkyl, aryl, heteroaryl, heterocyclyl, or optionally substituted variants thereof;
• each R7 and R8 is independently selected from H or alkyl, or R7 and R8 are joined together with the atom or atoms to which they are attached to form a heterocycle;
• each of the —(CH2)—o can be optionally substituted;
• and
• o is an integer between 1-50;
• (b) providing nucleotides to the surface of the substrate such that a detectable signal is generated when one or more nucleotides are utilized by the polynucleotide polymerase;
• (c) detecting signals at one or more polynucleotide clusters;
• and
• (d) repeating steps (b) and (c), thereby determining a nucleotide sequence of a polynucleotide present at the one or more polynucleotide clusters.