Small-Molecule/Polymer Recognition Triggers Aqueous-Phase Assembly and Encapsulation

Abstract

An aqueous-soluble melamine polymer was condensed into nanoparticles by specific heterocycle binding interactions with 5-fluorouracil (5-FU) or cyanuric acid (CA). Small-molecule/polymer recognition of this type exhibits a clear exothermic binding signature and is sufficiently robust to induce macromolecular assembly in water. Polymer amphiphiles with melamine sites in the hydrophobic block could be stably loaded with up to 17% weight 5-FU. Macromolecular assembly with 5-FU or CA requires specific hydrogen-bonding recognition between 5-FU/CA and polymer-displayed melamine; assembly may be blocked by melamine methylation. Melamine and 5-fluorouracil complexes were analyzed by X-ray crystal structure determination, which revealed the expected 5-FU/melamine hydrogen-bonding interactions.

Activated Ester Containing Polymers: Opportunities and Challenges for the Design of Functional Macromolecules

“…Those polymers selfassembled into micelles in water, featuring a carboxylic-acidfunctionalized hydrophobic core that endowed it with swelling/ deswelling properties upon pH regulation. To this end, Bong et al 187 synthesized PEG−polyacrylamide diblock copolymers comprised of a melamine-rich hydrophobic segment by treating a reactive PEG-b-PNHSA with aminoethylmelamine. Installation of melamine functionality within the block copolymer helped in structure formation in the presence of a complementary hydrogen-bonding small molecule such as 5-fluorouracil (5-FU) or cyanuric acid (CA).…”

Small Molecule Recognition Triggers Secondary and Tertiary Interactions in DNA Folding and Hammerhead Ribozyme Catalysis

“…5 We report herein design and synthesis of small molecule tren derivatives that trigger the global folding of unstructured nucleic acid; further, these motifs mediate tertiary interactions between oligo-U domains in partially folded RNA. Binding is brokered by the same melamine base previously reported in bPNA, a family of peptoid, 6 peptide, 7–11 and polyacrylates 12,13 that triplex hybridize with DNA/RNA via base tripling triazine recognition 14–18 with thymine/uracil. In contrast to artificial base pairs, 19–22 there are fewer examples of artificial base triples, 23 despite considerable interest in triplex structures.…”

A simple, highly sensitive, high throughput and organic solvent-free screening method for melamine by microsphere-based flow cytometry immunoassay

“…1 Aer obtaining CAAT, AETT was synthesized from it by Zhou's method. 17 Briey, ethylenediamine (3.1 g) was dissolved in water, followed by the addition of CAAT (1.45 g). The resulting mixture was heated to reux at 110 C overnight.…”