Long-acting antibacterial activity of quaternary phosphonium salts functionalized few-layered graphite

Tetradecyl triphenyl phosphonium bromide (TTP) functionalized few-layered graphite (FG) was prepared to investigate the effects of phosphonium salts usage on the characteristics, morphology, thermal stability and long-acting antibacterial property of TTP functionalized FG (TTP–FG) by introducing different content of TTP into FG. The results showed that the phosphonium salt was intercalated into FG, and the basal spacing of TTP–FG was enlarged with the increasing of phosphonium salt content. TTP–FG-3 with 33.7% (mass fraction) of TTP, displayed excellent thermal stability and long-acting antibacterial activity with the minimal inhibitory concentrations against E. coli and S. aureus of 580 mg L−1 and 285 mg L−1 after 72 h soaking, respectively.

Graphical abstractTTP–FG-3 with 38.7% (mass fraction) of TTP, displayed excellent thermal stability and long-acting antibacterial activity with the minimal inhibitory concentrations against E. coli and S. aureus of 580 mg L−1 and 285 mg L−1 after 72 h soaking, respectively.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights• Phosphonium salt (TTP) was intercalated into few-layered graphite (FG). • TTP–FGs displayed excellent thermal stability and long-acting antibacterial activity. • TTP–FG-3 soaked in saline water after 72 h, only 1.83 mass% of TTP is released. • MIC of TTP–FG-3 against E. coli and S. aureus is 580 and 280 mg L−1, respectively.