Hydra amphiphiles: Using three heads and one tail to influence aggregate formation and to kill pathogenic bacteria

作者：Gallagher Tara M; Marafino John N; Wimbish Brenden K; Volkers Brandi; Fitzgerald Gabriel; McKenna Kristin; Floyd Jason; Minahan Nicholas T; Walsh Brenna; Thompson Kirstie; Bruno David; Paneru Monica; Djikeng Sybelle; Masters Stephanie; Haji Suma; Seifert Kyle^*; Caran Kevin L^*

来源：Colloids and Surfaces B: Biointerfaces , 2017, 157: 440-448.

DOI：10.1016/j.colsurfb.2017.06.010

• Triple-headed amphiphiles
• Antibacterial
• Polycephalic
• Dendritic
• Thermodynamics of aggregation
• Conductivity
• Isothermal titration calorimetry
• Minimum inhibitory concentration
• Critical micelle concentration
• Structure activity relationship

Hydra amphiphiles mimic the morphology of the mythical multi-headed creatures for which they are named. Likewise, when faced with a pathogenic bacterium, some hydra derivatives are as destructive as their fabled counterparts were to their adversaries. This report focuses on eight new tricephalic (triple headed), single-tailed amphiphiles. Each amphiphile has a mesitylene (1,3,5-trimethylbenzene) core, two benzylic trimethylammonium groups and one dimethylalkylammonium group with a linear hydrophobe ranging from short (C8H17) to ultralong (C22H45). The logarithm of the critical aggregation concentration, log(CAC), decreases linearly with increasing tail length, but with a smaller dependence than that of ionic amphiphiles with fewer head groups. Tail length also affects antibacterial activity; amphiphiles with a linear 18 or 20 carbon atom hydrophobic chain are more effective at killing bacteria than those with shorter or longer chains. Comparison to a recently reported amphiphilic series with three heads and two tails allows for the development of an understanding of the relationship between number of tails and both colloidal and antibacterial properties.

• 出版日期2017-9-1