pH-Induced Amphiphilicity-Reversing Schizophrenic Aggregation by Alternating Copolymers

• DOI: 10.1021/acs.macromol.9b01804
• Publication Date: 2019-10-29T19:41:52Z
• Authors: Pintu Sar; Sipra Ghosh; Yulia D. Gordievs...; Krishna Gopal Gos...; Elena Yu. Kramarenko; Priyadarsi De
• Keywords: Chain transfer; Side chain

A series of copolymers with controlled monomer sequences are prepared via the reversible addition–fragmentation chain transfer polymerization tert-butyl carbamate (Boc)-l-alanine (VBA) and Boc-l-alanyl-l-leucine-conjugated styrenic (VBD) monomers l-alanine-appended maleimide (NMA). Monomer distribution in copolymer is examined by both 1H 13C NMR spectroscopy which eventually confirms an alternate placement different throughout polymer main copolymerization systems: VBA–NMA VBD–NMA. After successful expulsion pendant Boc groups, deprotected free −NH3+ −COOH functionalities side show pH-induced solubility transition pH range 3–8. As signified from analysis, this mainly associated a pH-dependent schizophrenic core–shell alteration aggregated structure aqueous solution also supported dynamic light scattering measurements showing variation hydrodynamic diameters aggregates at values. Scanning electron microscopy transmission further evidenced nature where significant morphological variations (from spherical micelles to vesicles or nearly wormlike aggregates) obtained as result varying value. The observed morphologies values explained computer simulations model hydrophobicity alternating groups. Such transitions enable us investigate their drug encapsulation sustained release behaviors depending on solution. To best our knowledge, first report shows behavior.