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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Structure-activity relationship for quaternary ammonium compounds hybridized with poly(methyl methacrylate)
Leticia D Melo1, Renata R Palombo, Denise F S Petri
1Biocolloids Lab, Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, CP 26077, CEP 05513-970, São Paulo/SP, Brazil.
ACS Applied Materials & Interfaces
|May 20, 2011
Summary
Hybrid films containing poly (methylmethacrylate) (PMMA) with quaternary ammonium compounds (QACs) showed varying biocidal activity. Cetyltrimethylammonium bromide (CTAB) offered the best antibacterial performance due to optimal diffusion and balance.
Area of Science:
- Materials Science
- Polymer Chemistry
- Antimicrobial Materials
Background:
- Poly (methylmethacrylate) (PMMA) is a versatile polymer.
- Quaternary ammonium compounds (QACs) are known for their antimicrobial properties.
- Hybrid materials combining polymers and QACs offer potential for enhanced functionalities.
Purpose of the Study:
- To investigate the properties and biocidal activity of PMMA-based hybrid films.
- To characterize the influence of different QACs (DODAB, CTAB, TPAB) on film characteristics and antimicrobial efficacy.
- To correlate QAC mobility and film properties with antibacterial activity against Pseudomonas aeruginosa and Staphylococcus aureus.
Main Methods:
- Film characterization using wettability, ellipsometry, and atomic force microscopy.
- Assessment of active compound diffusion into water.
- Surface analysis via X-ray photoelectron spectroscopy (XPS).
- Evaluation of biocidal activity against specific bacterial strains.
Main Results:
- QAC mobility within the PMMA films increased in the order DODAB < CTAB < TPAB.
- Cetyltrimethylammonium bromide (CTAB) exhibited the highest bioactivity, attributed to optimal diffusion and hydrophobic-hydrophilic balance.
- Dioctadecyldimethylammonium bromide (DODAB) demonstrated surface-immobilized activity, killing bacteria on contact, while tetrapropylammonium bromide (TPAB) showed reduced efficacy due to unfavorable balance.
Conclusions:
- The choice of QAC significantly impacts the performance of PMMA-based hybrid films.
- Optimal diffusion and hydrophobic-hydrophilic balance are crucial for achieving high biocidal activity.
- Specific QACs like CTAB and DODAB can be tailored for different antimicrobial applications, such as diffusion-based or contact-killing mechanisms.
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