kth.sePublications KTH
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Heterofunctional Polyester Dendrimers as Architecturally Tunable Platforms for Therapeutic Applications
KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.ORCID iD: 0000-0003-1683-6016
2025 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Dendrimers have emerged as versatile platforms in nanomedicine due to their well-defined architecture, monodispersity, and multivalent nature. However, conventional designs confine functional groups to the periphery, limiting their chemical and therapeutic diversity. This thesis presents heterofunctional polyester dendrimers (HFDs) based on a novel bromide-functional AB2C monomer as a multifunctional platform, combining molecular precision with clinical potential. The synthetic route follows divergent anhydride-mediated esterification, yielding monodisperse dendrimers (polydispersity ≤1.03) with internal bromide or azide groups and external hydroxyl functionalities. The biodegradable polyester scaffold undergoes controlled degradation over 30–96 h, balancing stability with biocompatibility. Orthogonal post-functionalization (azide-alkyne click chemistry and thiol-bromo coupling) enables selective incorporation of diverse payloads. Ammonium groups or apolar drugs like diclofenac can be embedded internally, while cationic groups or PEG chains are introduced onto the surface via esterification.

Systematic biological evaluation across antibacterial, gene delivery, and anticancer applications reveals a unifying principle: the therapeutic efficacy is governed by spatial distribution of functionalities rather than dendrimer generation. In antibacterial applications, dual-charge dendrimers display potent activity (MIC: 10–21 μM) against Gram-positive and Gram-negative pathogens with enhanced E. coli sensitivity, maintaining >85% mammalian cell viability (3–100-fold improvement over homofunctional counterparts). For gene therapy, the same cationic architecture achieves 93% RNase protection and 62% gene silencing in glioblastoma cells with minimal cytotoxicity. In anticancer applications, covalent diclofenac conjugation with PEGylation induces selective ROS-mediated cytotoxicity at 16–32-fold lower concentrations than free diclofenac, preserving >95% normal cell viability.

This work demonstrates that therapeutic performance can be decoupled from generation number through rational architectural design. The HFD platform defines transferable design principles for next-generation nanomedicine, uniting polymer versatility with molecular precision.

Abstract [sv]

Dendrimerer har inom nanomedicin utvecklats till mångsidiga plattformar tack vare deras väldefinierade struktur, monodispersitet och multivalenta karaktär. I konventionella dendrimerer är dock de funktionella grupperna begränsade till periferi­strukturen, vilket inskränker deras kemiska och terapeutiska mångfald. Denna avhandling presenterar heterofunktionella polyesterdendrimer (HFD) baserade på en ny bromid-funktionell AB2C-monomer som en multifunktionell plattform som kombinerar molekylär precision med klinisk potential. Den syntetiska strategin följer divergent anhydrid-medierad esterifiering, vilket ger monodispersa dendrimerer (polydispersitet ≤1,03) med interna bromid- eller azidgrupper och externa hydroxylgrupper. Det biologiskt nedbrytbara polyesterskelettet genomgår kontrollerad nedbrytning under 30–96 timmar, vilket ger en balans mellan stabilitet och biokompatibilitet. Ortogonal post-funktionalisering (azid-alkyn-klickkemi och tiol-brom-koppling) möjliggör selektiv inkorporering av olika nyttolaster. Ammoniumgrupper eller apolära läkemedel som diklofenak kan inbäddas internt, medan kationiska grupper eller PEG-kedjor introduceras på ytan via esterifiering.

Systematiska biologiska utvärderingar inom antibakteriella tillämpningar, genterapi och cancerbehandling uppvisar en gemensam princip: den terapeutiska effektiviteten styrs av den rumsliga fördelningen av funktionella grupper snarare än dendrimergeneration. Inom antibakteriella tillämpningar uppvisar dendrimerer med dubbel laddning potent aktivitet (MIC: 10–21 μM) mot både grampositiva och gramnegativa patogener med förhöjd E. coli-känslighet, samtidigt som >85 % av däggdjurscellers viabilitet bevaras (3–100 gånger bättre än homofunktionella motsvarigheter). Inom genterapi ger samma katjoniska arkitektur 93 % RNas-skydd och 62 % gen­ned­tystning i gliobasalomceller med minimal cytotoxicitet. Inom cancerbehandling leder kovalent diklofenak-konjugering i kombination med PEGylering till selektiv ROS-medierad cytotoxicitet vid 16–32 gånger lägre koncentrationer än fri diklofenak, vilket bevarar >95 % av normalcellernas viabilitet.

Detta arbete visar att terapeutisk prestanda kan frikopplas från dendrimer-generation genom rationell arkitektonisk design. HFD-plattformen definierar överförbara designprinciper för nästa generations nanomedicin, vilket förenar polymerers flexibilitet med molekylär precision.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2025. , p. 127
Series
TRITA-CBH-FOU ; 2025:38
Keywords [en]
Nanomedicine, heterofunctional polyester dendrimers, architectural design, orthogonality, click chemistry, biodegradability, antimicrobial resistance, gene delivery, drug repurposing, cytotoxicity.
Keywords [sv]
Nanomedicin, heterofunktionella polyesterdendrimer, arkitektonisk design, ortogonalitet, klickkemi, biologisk nedbrytbarhet, antimikrobiell resistens, gentransport, läkemedelsomvandling, cytotoxicitet.
National Category
Nanotechnology for/in Life Science and Medicine
Research subject
Fibre and Polymer Science
Identifiers
URN: urn:nbn:se:kth:diva-373178ISBN: 978-91-8106-490-2 (print)OAI: oai:DiVA.org:kth-373178DiVA, id: diva2:2015380
Public defence
2026-01-09, Kollegiesalen, https://kth-se.zoom.us/j/69760264313, Brinellvägen 8, Stockholm, 10:00 (English)
Opponent
Supervisors
Funder
Swedish Research Council
Note

QC 2025-11-28

Embargo t.o.m. 2027-01-09 godkänt av skolchef Amelie Eriksson Karlström via e-post 2025-12-01.

Available from: 2025-11-28 Created: 2025-11-20 Last updated: 2025-12-08Bibliographically approved
List of papers
1. Synthesis, evaluation and modification of heterofunctional polyester dendrimers with internally queued bromide groups
Open this publication in new window or tab >>Synthesis, evaluation and modification of heterofunctional polyester dendrimers with internally queued bromide groups
Show others...
2024 (English)In: Soft Matter, ISSN 1744-683X, E-ISSN 1744-6848, Vol. 20, no 38, p. 7573-7577Article in journal (Refereed) Published
Abstract [en]

Heterofunctional polyester dendrimers up to the third generation, containing 21 internally queued bromine atoms, have been successfully synthesized for the first time using a divergent growth approach. Direct azidation reactions enabled the conversion of the bromide groups to clickable azide pendant functionalities. Therapeutic and chemical moeities could then be coupled to the internal azide or bromide functionalities and external hydroxyl groups of the heterofunctional dendrimers through CuAAC, thiol-bromo click and esterification reactions, expanding their potential for biomedical applications.

Place, publisher, year, edition, pages
Royal Society of Chemistry (RSC), 2024
National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-354899 (URN)10.1039/d4sm00849a (DOI)001315077900001 ()39295579 (PubMedID)2-s2.0-85205604524 (Scopus ID)
Note

QC 20241022

Available from: 2024-10-16 Created: 2024-10-16 Last updated: 2025-11-20Bibliographically approved
2. Heterofunctional Cationic Polyester Dendrimers as Antibacterial Agents: The Role of Internal and External Charges
Open this publication in new window or tab >>Heterofunctional Cationic Polyester Dendrimers as Antibacterial Agents: The Role of Internal and External Charges
2025 (English)In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 26, no 9, p. 6164-6176Article in journal (Refereed) Published
Abstract [en]

Antimicrobial resistance is a global health crisis, necessitating novel antibacterial strategies. Polycations, particularly polyester dendrimers, are promising due to their structural precision and membrane-disruptive mechanisms. However, existing dendrimers lack versatility in charge distribution, limiting their antibacterial efficacy. Here, we report two families of cationic polyester dendrimers (up to the third generation) with either internal or combined internal and external charges compared with traditional bis-MPA dendrimers bearing only external cations. These heterofunctional dendrimers, built from AB2C monomers, carry up to 45 charges at the highest generation. Internal propargyl amines were introduced via CuAAC chemistry, while external β-alanine provided complementary charges in the second family. Dendrimers with both internal and external charges showed superior antibacterial activity against Gram-positive and Gram-negative bacteria while maintaining biocompatibility. The second-generation dendrimer (G2-(PA-NH3+)9-(β-Ala-NH3+)12) exhibited bacteriostatic and bactericidal activity at 10–21 μM and enhanced Escherichia coli sensitivity, with favorable biodegradation, highlighting their promise as antimicrobials where charge distribution is key for efficacy.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2025
National Category
Polymer Chemistry
Identifiers
urn:nbn:se:kth:diva-370698 (URN)10.1021/acs.biomac.5c01094 (DOI)001544477200001 ()40763327 (PubMedID)2-s2.0-105015495959 (Scopus ID)
Note

QC 20250930

Available from: 2025-09-30 Created: 2025-09-30 Last updated: 2025-11-20Bibliographically approved
3. Heterofunctional Cationic Polyester Dendrimers as Potent Nonviral Vectors for siRNA Delivery
Open this publication in new window or tab >>Heterofunctional Cationic Polyester Dendrimers as Potent Nonviral Vectors for siRNA Delivery
Show others...
2025 (English)In: Pharmaceutics, E-ISSN 1999-4923, Vol. 17, no 11, p. 1476-1476Article in journal (Refereed) Published
Place, publisher, year, edition, pages
MDPI AG, 2025
National Category
Nanotechnology for/in Life Science and Medicine
Identifiers
urn:nbn:se:kth:diva-373176 (URN)10.3390/pharmaceutics17111476 (DOI)
Funder
Swedish Research Council, 2020-04339Swedish Research Council, 2024-05260European Commission, 101064084
Note

QC 20251124

Available from: 2025-11-20 Created: 2025-11-20 Last updated: 2025-11-24Bibliographically approved
4. Repurposing Diclofenac via PEGylated Heterofunctional Dendrimers for ROS-Mediated Anticancer Effects
Open this publication in new window or tab >>Repurposing Diclofenac via PEGylated Heterofunctional Dendrimers for ROS-Mediated Anticancer Effects
(English)Manuscript (preprint) (Other academic)
National Category
Nanotechnology for/in Life Science and Medicine
Identifiers
urn:nbn:se:kth:diva-373177 (URN)
Note

QC 20251124

Available from: 2025-11-20 Created: 2025-11-20 Last updated: 2025-11-24Bibliographically approved

Open Access in DiVA

The full text will be freely available from 2027-01-09 09:55
Available from 2027-01-09 09:55

Authority records

Singh, Arunika

Search in DiVA

By author/editor
Singh, Arunika
By organisation
Coating Technology
Nanotechnology for/in Life Science and Medicine

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 1477 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf