Cysteine-based amphiphilic peptide-polymer conjugates via thiol-mediated radical polymerization: Synthesis, self-assembly, RNA polyplexation and N-terminus fluorescent labeling for cell imaging

Amphiphilic Perylene Bisimide–Polymer Conjugates by Cysteine-Based Orthogonal Strategy: Vesicular Aggregation, DNA Binding, and Cell Imaging

“…Therefore, one should expect disaggregation of the conjugate molecules to their monomeric form as observed by some research groups. , However, in this case, the appearance of the broad absorption peak can be ascribed to the aggregation of conjugate molecules due to the presence of H-bonding interaction between the protons of a partially protonated “N” atom of the imidazole ring of PVim chain and the “N” atom of the imidazole moiety of the neighboring PVim chain (Scheme S1). The spectral pattern of the conjugate in the pH ranges of 7.0–11.0 was typical of the π–π stacking aggregation of PBI moiety of PBI–(Cys–PVim-II) 2 as there was no protonation and hence no H-bonding interaction between the attached PVim chains.…”

“…The zeta potential (ξ) value of +8.5 mV of this conjugate solution implied its cationic nature (Figure S31). It is known that cationic polymers interact with DNA/RNA, which leads to the formation of polyplexes having applications in delivering DNA/RNA to cells. , Therefore, it is expected that this cationic PBI–(Cys–PVim) 2 can also bind with negatively charged DNA through electrostatic interactions to form a stable polyplex. Furthermore, the low toxicity of this biocompatible conjugate provided a clear advantage of employing this as a carrier for DNA to living cells.…”

“…In this direction, highly water-soluble biocompatible PBI–polymer conjugates with low cytotoxicity were developed to use them as fluorescent probes for labeling of living cells. ,,,,, PBIs containing hydrophilic small molecules have also been used for labeling of living cells and for other biological applications. ,− Beside cell imaging applications, the binding capability of water-soluble PBI-small molecular conjugates with DNA has also been studied by many research groups. ,,, However, most of these studies were focused on the investigation of intercalations of PBIs with DNA as well as their applications in living cell. Furthermore, it is also known that cationic/noncationic polymers can form stable polyplexes with DNA/RNA through electrostatic interactions, which have been studied in detail by several researchers including our groups. − Therefore, the binding of amphiphilic PBI–polymer conjugate with DNA would certainly be interesting to study.…”

Self-Assembly Peptides-a Review

“…The authors confirmed polytyrosine-g-poly(2-ethyl-2-oxazoline) graft copolymer conjugates micelles to be a good candidate in drug delivery systems. There has been significant interest in the synthesis of peptide-polymer bioconjugate materials, thus, Dule et al (2017) examined the synthesis of a watersoluble amphiphilic peptide-poly (1-vinylimidazole) bioconjugate. The bioconjugate was synthesized by the "grafting from" method based on thiol-mediated radical polymerization and was investigated using 1H-NMR spectroscopy, field emission scanning electron microscopy, ESI mass spectrometry, dynamic light scattering, transmission electron microscopy, MALDITOF, fluorescence spectroscopy, zeta potential, and critical aggregation concentration measurement.…”

Peptide‐Engineered Fluorescent Nanomaterials: Structure Design, Function Tailoring, and Biomedical Applications

“…designed a novel amphiphilic bioconjugate that formed by a hydrophobic dipeptide sequence Boc‐Cys‐Trp‐OMe linked with a water‐soluble polyvinyl imidazole (PVim) segment employing “grafting from” strategy based on thiol‐mediated radical polymerization. [ 87 ] Specifically, a tetrapeptide [(Boc‐Cys‐Trp‐OMe) 2 ] with two adjacent cysteine residues was first synthesized through coupling reaction. Then, the dipeptide was prepared by reduction of disulfide bond of the tetrapeptide using dithiothreitol (DTT).…”