umu.sePublications
Change search
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
Preparation of Antifouling Polymer Brushes Functionalized with Gallium Salicylidene Acylhydrazide Complexes
Umeå University, Faculty of Science and Technology, Department of Chemistry.
Umeå University, Faculty of Science and Technology, Department of Physics.
Umeå University, Faculty of Science and Technology, Department of Chemistry.
(English)Manuscript (preprint) (Other academic)
National Category
Chemical Sciences
Identifiers
URN: urn:nbn:se:umu:diva-107750OAI: oai:DiVA.org:umu-107750DiVA: diva2:849359
Available from: 2015-08-28 Created: 2015-08-28 Last updated: 2015-09-01
In thesis
1. Antivirulent and antibiofilm salicylidene acylhydrazide complexes in solution and at interfaces
Open this publication in new window or tab >>Antivirulent and antibiofilm salicylidene acylhydrazide complexes in solution and at interfaces
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The growing bacterial resistance against antibiotics creates a limitation for using traditional antibiotics and requests development of new approaches for treatment of bacterial infections. Among the bacterial infections that are most difficult to treat, biofilm-associated infections are one of the most hazardous. Consequently, the prevention of biofilm formation is a very important issue. One of the techniques that are widely investigated nowadays for this purpose is surface modification by polymer brushes that allows generating antifouling antibacterial surfaces. Previously, it was reported that salicylidene acylhydrazides (hydrazones) are good candidates as antivirulence drugs targeting the type three secretion system (T3SS). This secretion system is used by several Gramnegative pathogens, including Pseudomonas aeruginosa, to deliver toxins into a host cell. Furthermore, the chemical structure of these substances allows formation of complexes with metal ions, such as Fe3+ and Ga3+. The antibacterial activity of Ga3+ is well known and attributed to its similarity to the Fe3+ ion. It has also been shown that Ga3+ ions are able to suppress biofilm formation and growth in bacteria. In this thesis the chemistry of antibacterial and antivirulence Ga3+-Hydrazone complexes in solution was studied. First, to get insights in the solution chemistry, the protonation and the stability constants as well as the speciation of the Ga3+-Hydrazone complexes were determined. Additionally, a procedure for anchoring one of the hydrazone substances to antifouling polymer brushes was optimized, and the resulting surfaces were characterized. Results showed that the complexation with Ga3+ ions stabilizes the ligand and increases its solubility. Ga3+ ion binds to the hydrazone molecule forming a strong chelate that should be stable at physiological conditions. The different biological assays, such as Ga3+ uptake, antivirulence and antibiofilm effects, indicated very complex interaction of these complexes with the bacterial cell. Negatively charged and zwitterionic surfaces strongly reduced protein adsorption as well as biofilm formation. Therefore, the antifouling zwitterionic poly-[2-(methacryloyloxy)ethyl]dimethyl-3- sulfopropyl)-ammonium hydroxide (pMEDSAH) brushes were post-modified and successfully functionalized with bioactive substances via a block-copolymerization strategy. However, in order to maintain the availability of the bioactive substance after functionalization, the hydrophobic polyglycidylmethacrylate (pGMA) top block is probably better to functionalize with a lipophilic molecules to reduce diblock copolymer brush rearrangement.

Place, publisher, year, edition, pages
Umeå: Umeå University, 2015. 84 p.
Keyword
Antivirulent, Antibiofilm, Hydrazones, Gallium, Pseudomonas aeruginosa, Type three secretion system, Equilibrium constant, Chemical equilibrium modelling, Spectrophotometric titration, UV-Vis
National Category
Chemical Sciences
Identifiers
urn:nbn:se:umu:diva-107889 (URN)978-91-7601-307-6 (ISBN)
Public defence
2015-09-24, KB3B1 KBC, Umeå, 10:00 (English)
Opponent
Supervisors
Available from: 2015-09-03 Created: 2015-08-28 Last updated: 2015-09-01Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Hakobyan, ShoghikBarbero, David R.Ramstedt, Madeleine
By organisation
Department of ChemistryDepartment of Physics
Chemical Sciences

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 272 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