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Updated: May 30, 2026

Attaching Biological Probes to Silica Optical Biosensors Using Silane Coupling Agents
Published on: May 1, 2012
Synthesis and antimicrobial activity of quaternary ammonium silane coupling agents
Norio Yoshino1, Shigenori Sugaya, Toshimitsu Nakamura
1Faculty of Engineering, Tokyo University of Science, Tokyo, Japan. yoshino@ci.kagu.tus.ac.jp
Abstract:
Fourteen novel silane coupling agents with a quaternary ammonium group introduced into the molecule, [CH(2)=CHCH(2)N(+)(CH(3))(C(n)H(2n+1))(CH(2))(3)Si(OCH(3))(3)]X(-) (n-X, n=10-18, X=Cl, Br, or I), were synthesized with the aim of using these agents to make material surfaces antimicrobial for a long period of time. Measurements of the minimum inhibitory concentrations (MIC) against 12 kinds of fungi and bacteria revealed that the coupling agent with a C(10) alkyl chain and Cl- or Br- counter-ion (10-Cl or 10-Br) has the highest antimicrobial activity among the n-X agents synthesized, but 14-Cl and 14-Br showed the highest activity on a modified porcelain plate.
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