Dithienylpyrrole-based biosensors and methods for their preparation and use

A composition comprising a dithienylpyrrole polymer, wherein the dithienylpyrrole polymer comprises at least two of the monomer units represented by Formula Ia:

• wherein:
• Z is a bivalent hydrocarbyl group selected from the group consisting of alkylene, alkenylene and alkynylene;
• R1, R2, R3, and R4 are each independently C1-C6 alkyl, C2-C6 alkylene, C2-C6 alkyne, hydrogen or halogen;
• and
• R5, R6, R7, and R8 are each independently C1-C10 alkyl, C2-C10 alkylene, C1-C10 alkyne, hydrogen, or halogen.

A method for the preparation of a nanostructure film on a surface of a substrate, comprising:

• forming a composition comprising dithienylpyrrole monomers, at least one metal precursor, at least one organic solvent, at least one supporting electrolyte, and at least one amine compound;
• allowing metal nanostructures to form in the composition;
• and
• contacting the composition with a substrate under a condition effective to covalently bound two or more dithienylpyrrole monomers to form a dithienylpyrrole polymer and forming the nanostructure film on at least a portion of a surface of the substrate.

A biosensor, comprising:

• a working electrode configured to immobilize a bioreactive material, wherein the bioreactive material is reactive with a target material, wherein the working electrode comprises a dithienylpyrrole polymer and metal nanostructures, wherein the dithienylpyrrole polymer comprises at least two of the monomer units represented by Formula Ia:
• wherein:
• Z is a bivalent hydrocarbyl group selected from the group consisting of alkylene, alkenylene and alkynylene;
• R1, R2, R3, and R4 are each independently C1-C6 alkyl, C2-C6 alkylene, C2-C6 alkyne, hydrogen or halogen;
• and
• R5, R6, R7, and R8 are each independently C1-C10 alkyl, C2-C10 alkylene, C1-C10 alkyne, hydrogen, or halogen.

A method for detecting an analyte in a sample, the method comprising:

• providing a sample suspected of containing the analyte;
• contacting the sample with a biosensor, wherein the biosensor comprises a reference electrode and a working electrode configured to immobilize a bioreactive material, wherein the bioreactive material is reactive with the analyte, wherein the working electrode comprises a dithienylpyrrole polymer and metal nanostructures, wherein the dithienylpyrrole polymer comprises at least two of the monomer units represented by Formula Ia:
• wherein:
• Z is a bivalent hydrocarbyl group selected from the group consisting of alkylene, alkenylene and alkynylene;
• R1, R2, R3, and R4 are each independently C1-C6 alkyl, C2-C6 alkylene, C2-C6 alkyne, hydrogen or halogen;
• and
• R5, R6, R7, and R8 are each independently C1-C10 alkyl, C2-C10 alkylene, C1-C10 alkyne, hydrogen, or halogen.

A method for the preparation of a compound represented by Formula I, comprising:

• i. contacting an optionally substituted thiophene
• with a succinyl chloride
• to obtain a first intermediate
• ii. contacting the first intermediate
• with a cyanoaniline
• to obtain a second intermediate
• iii. hydrolyzing the nitrile group of the second intermediate
• to obtain the compound of Formula I
• wherein:
• Z is a bivalent hydrocarbyl group selected from the group consisting of alkylene, alkenylene and alkynylene;
• R1, R2, R3, and R4 are each independently C1-C6 alkyl, C2-C6 alkylene, C2-C6 alkyne, hydrogen or halogen;
• and
• R5, R6, R7, and R8 are each independently C1-C10 alkyl, C2-C10 alkylene, C1-C10 alkyne, hydrogen, or halogen.