Synthesis of a Series of Folate-Terminated Dendrimer-b-PNIPAM Diblock Copolymers: Soft Nanoelements That Self-Assemble into Thermo- and pH-Responsive Spherical Nanocompounds

Author(s)

Bertuzzi, Diego L. ; Morris, Melody A. ; Braga, Carolyne B. ; Olsen, Bradley D. ; Ornelas, Catia

• Document type: Journal article
• Source: MACROMOLECULES; v. 55, n. 7, p. 16-pg., 2022-04-12.

Abstract

A series of well-defined bifunctional dendrimers bearing one azide and 5,15, and 44 folate termini were synthesizedviathe divergent approach. Poly(N-isopropylacrylamide) homopolymers PNIPAM-7k, PNIPAM-19k, and PNIPAM-64kwere prepared using the reversible addition-fragmentation chain-transfer polymerization(60-67% yield) followed by end functionalization with a cyclooctyne derivative. Agrafting-to approach through strain-promoted azide alkyne cycloaddition between thedendrimers and the PNIPAM afforded a series of dendrimer-b-PNIPAM diblockcopolymers containing folates (G1-11k, G2-30k, and G3-95k). Investigation of the self-assembly process in aqueous media revealed the formation of thermo- and pH-responsivecore-shell spherical micelles within the 70-160 nm size range with low polydispersities.Within the nanoperiodic concept, these dendrimer-b-PNIPAM copolymers behave as S1-type nanoelements that self-assemble into soft:soft spherical nanocompounds with alinear relationship between the molecular weight of the copolymers and thehydrodynamic diameter of the self-assembled nanospheres. The thermo- and pH-responsiveness of the micelles formed by the dendrimer-b-PNIPAM diblock copolymers bearing folates make them promising candidates for targeted drug delivery (AU)

• FAPESP's process: 15/04929-0 - Development of biosensors for instantaneous detection of proteins and cancer cells, for application on on-site biopsy
• Grantee: Diego Luan Bertuzzi
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 14/50906-9 - INCT 2014: in Functional Complex Materials
• Grantee: Fernando Galembeck
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 21/00555-9 - Development of polymeric nanoparticles and multifunctional dendrimers for drug delivery
• Grantee: Igor Dias Jurberg
• Support Opportunities: Regular Research Grants