Substrate, and preparation method therefor and use of substrate

A method for preparing a substrate having a polymer coating on a surface thereof, comprising:

• making a polymer in contact with the surface to allow the polymer to be linked to the surface, wherein the polymer comprises a repeating unit A of formula I and a repeating unit B of formula II or formula III:
• wherein:
• X is selected from —O— and —NH—;
• R01′, R01″, and R01′″ are each independently selected from —H and C1-C3 alkyl;
• R0 is selected from C1-C10 alkyl and —(C1-C5 alkyl)-NH—NHS-PEG4, and R0 comprises at least one R02 substituent, wherein at least one R02 substituent is each independently selected from epoxy, amino, and azido;
• R03′, R03″, R03′″, R03″″, R04′, R04″, R04′″, R05′, R05″, and R05′″ are each independently selected from —H, C1-C3 alkyl, amido, and an ester group;
• L1 is selected from C1-C3 alkylene and —C(O)—R06—C(O)—;
• and
• R06 is selected from PEG and alkyl diamine, provided that when R06 is PEG, the PEG has a molecular weight of 200-2000.

A method for capturing and/or detecting a biomolecule comprising:

• contacting the biomolecule with a substrate having a surface, the surface comprising a polymer coating covalently linked thereto, wherein the polymer coating comprises a polymer comprising a repeating unit A of formula I and a repeating unit B of formula II or formula III:
• wherein:
• X is selected from —O— and —NH—;
• R01′, R01″, and R01′″ are each independently selected from —H and C1-C3 alkyl;
• R0 is selected from C1-C10 alkyl and —(C1-C5 alkyl)-NH—NHS-PEG4, and R0 comprises at least one R02 substituent, wherein at least one R02 substituent is each independently selected from epoxy, amino, and azido;
• R03′, R03″, R03′″, R03″″, R04′, R04″, R04″″, R05′, R05″, and R05′″ are each independently selected from —H, C1-C3 alkyl, amido, and an ester group;
• L1 is selected from C1-C3 alkylene and —C(O)—R06—C(O)—;
• and
• R06 is selected from PEG and alkyl diamine, and provided that when R06 is PEG, the PEG has a molecular weight of 200-2000.