Self-Assembly of DNA-Coupled Semiconducting Block Copolymers

Abstract

We describe the synthesis and self-assembly of amphiphilic semiconducting polymers composed of a polythiophene derivative (i.e., poly [3-(2,5,8,11-tetraoxatridecanyl)thiophene] (PTOTT)) and an oligonucleotide, DNA-b-PTOTT. These new bioconjugated polymers combine the excellent optoelectronic properties of semiconducting polymers and the programmable molecular recognition properties of DNA. Because of the unique combination of rigid polythiophene and highly negatively charged DNA, they self-assemble into size-controllable vesicles in water. DNA-modified one-dimensional polythiophene nanoribbons were formed by simultaneous assembly of DNA-b-PTOTT with PEG-b-PTOTT, demonstrating that various types of DNA-modified functional nanostructures can be formed by the mixed assembly. This approach offers a new pathway to couple various types of soft optoelectronic nanostructures with DNA's molecular recognition properties.

Recent advances in the solution self‐assembly of amphiphilic “rod‐coil” copolymers

“…Based on these affecting factors, this subsection starts with the description of controllable self‐assembly of amphiphilic rod‐coil linear BCPs containing thiophene type blocks, as they represent the most extensively studied π‐conjugated polymer system in recent years . For example, Patra et al synthesized poly(3‐hexylthiophene)‐ block ‐poly(dimethylsiloxane) (P3HT‐ b ‐PDMS) diblock copolymers .…”

“…Comparison of the thicknesses and the average dimension of the diblock macromolecules as well as the blue‐shifted spectral absorptions indicated that PTOTT blocks probably adopted the H‐aggregation mode in the 2D nanostructures. Interestingly, this group also synthesized another new conjugated diblock copolymer, PTOTT‐ b ‐DNA . This copolymer self‐assembled into vesicles with a PTOTT wall and DNA coronae in water; the average size of the vesicles was controllable over a broad length scale from a couple of 100 nm to over a micrometer by varying the concentration of the copolymers.…”

“…In addition, PTOTT‐ b ‐DNA showed a salt‐induced reversible morphology transition from vesicles to lamellae due to the screening of negative charges on the phosphate backbone of DNA. The co‐assembly of PTOTT‐ b ‐DNA and PTOTT‐ b ‐PEG resulted in the formation of nanoribbons modified with DNA, which provides a new pathway to combine organic semiconducting nanostructures with the molecular recognition functions of DNA …”

Organic–inorganic rod–coil block copolymers comprising substituted polyacetylene and poly(dimethylsiloxane) segments

“…An important class of mesogen-bearing block copolymers is those containing mesogen-jacketed liquid crystalline polymers (MJLCPs), [19][20][21] which were synthesized mostly through controlled/"living" radical polymerizations of designed monomers with laterally attached mesogenic side groups. Furthermore, π-electron conjugated polymers, such as polythiophenes, [37][38][39][40] poly( phenylene vinylene), 3,41-45 poly-( phenylquinoline), 46-48 polyfluorene, 49-53 polyacetylene, [54][55][56][57][58] etc., were also used as rod segments in rod-coil block copolymers. 29 Main-chain liquid crystalline polymers 30 and oligomers [31][32][33][34][35][36] have also been employed as straightforward candidates for rod-like segments in rod-coil block copolymers.…”

DNA‐Grafted Supramolecular Polymers: Helical Ribbon Structures Formed by Self‐Assembly of Pyrene–DNA Chimeric Oligomers

“…[1][2][3][4][5][6][7][8][9][10][11][12] Themerging of organic entities,such as polymers, [13] lipid chains, [14,15] or aromatic molecules [16][17][18][19][20][21][22][23][24] with DNAmotifs enables the design and engineering of supramolecular architectures with special optical, mechanical, or biological properties. [32][33][34][35] In DNA-grafted polymers [36] (Scheme 1A)o ligonucleotides are arranged in ac omb-like fashion on ap olymer backbone. [32][33][34][35] In DNA-grafted polymers [36] (Scheme 1A)o ligonucleotides are arranged in ac omb-like fashion on ap olymer backbone.…”