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PH-Responsive Schizophrenic Diblock Copolymers Prepared by Polymerization-Induced Self-Assembly.

ABSTRACT: Polymerization-induced self-assembly (PISA) is used for the highly convenient and efficient preparation of ampholytic diblock copolymer nanoparticles directly in acidic aqueous solution. Cationic nanoparticles comprising a protonated polyamine stabilizer block and a hydrophobic polyacid core-forming block are formed at pH 2. Micelle inversion occurs at pH 10 to produce anionic nanoparticles with an ionized polyacid stabilizer block and a hydrophobic polyamine core-forming block. Macroscopic precipitation occurs at around pH 6-7, which lies close to the isoelectric point of this ampholytic diblock copolymer. Incorporation of fluorescein and rhodamine dye labels into the acid and amine blocks, respectively, leads to dual-color bifluorescent self-reporting pH-responsive nanoparticles.

SUBMITTER: Canning SL

PROVIDER: S-EPMC5577634 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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pH-Responsive Schizophrenic Diblock Copolymers Prepared by Polymerization-Induced Self-Assembly.

Canning Sarah L SL Neal Thomas J TJ Armes Steven P SP

Macromolecules 20170801 16

Polymerization-induced self-assembly (PISA) is used for the highly convenient and efficient preparation of ampholytic diblock copolymer nanoparticles directly in acidic aqueous solution. Cationic nanoparticles comprising a protonated polyamine stabilizer block and a hydrophobic polyacid core-forming block are formed at pH 2. Micelle inversion occurs at pH 10 to produce anionic nanoparticles with an ionized polyacid stabilizer block and a hydrophobic polyamine core-forming block. Macroscopic prec ...[more]

PMID: 28867829

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