Study on Surface Activity and Bacteriostasis of a Series of Gemini Cationic Surfactants

Abstract

0 N 0 -tetramethyl-dichloride has been synthesized with R (CH 3 ) 2 N (R = C n H 2nþ1 , n ¼ 12, 14, 16), hydrogen chloride and epoxy chloropropane as raw materials. The products have been characterized by element analysis and 1 H NMR spectra. Fundamental interfacial behavior of the surfactant at the air/water interface has been investigated by means of surface tension measurements to provide an insight into relationship between the structure of the hydrophobic moiety and the surfactant properties. Foam performance and bacteriostasis in aqueous solution have been investigated. The results indicate that the gemini cationic surfactants have strong surface activity. The surface activity is relevant to the number of carbon atoms in the hydrophobic tail of surfactant molecule. The longer the alkyl chain is, the stronger the surface activity and the lower the critical micelle concentration will be. G 12 Cl 2 solution possesses the best performance of the foaming ability and foam stability at 298.15 K, but bubbly and stability efficiency is the lowest among the three systems. Bacteriostasis of the surfactants has been determined with disk diffusion on filter paper. The results show that all of the newly synthesized double quaternary ammoniums possess quite good bacteriostasis.

Synthesis, Surface and Antimicrobial Activities of Novel Cationic Gemini Surfactants

“…It can also be seen from the MIC values presented in Table 2 that increasing the hydrophobic chain length of the novel cationic gemini surfactants provides an increase in activity especially against C. albicans [14,15]. This may be because the surface activity of the novel cationic gemini surfactants increases with increasing hydrophobic chain length.…”

“…Additionally, the MIC value of 3c is closer to its CMC value. Thus, the molecules of 3c are more easily accumulated in the interface and absorbed on the surface of the microorganisms [15], and the antimicrobial activity of 3c is stronger.…”

“…Among gemini surfactants, bis-quaternary ammonium compounds have been the most extensively investigated by researchers. The reason for this may be that the cationic gemini surfactants can be prepared through relatively simple synthetic pathways and in high chemical yields, show excellent surface-active properties [6][7][8][9][10], and possess strong antimicrobial activities [11][12][13][14][15][16][17]. To date the majority of gemini surfactant studies have been focused on the nature of the spacer group (short or long, flexible or rigid, hydrophilic or hydrophobic) and the length and structure of their hydrophobic chains [18][19][20].…”

Green Synthesis, Surface Activity, Micellar Aggregation, and Corrosion Inhibition Properties of New Gemini Quaternary Ammonium Surfactants

“…As is seen in Table , the γ CMC values of these surfactants are between 28.21 and 29.77 mN·m –1 . Compared with the γ CMC values of some gemini quaternary ammonium surfactants that have been reported, which are usually greater than 30 mN·m, –1 , − these values are lower, indicating that the surface activities of these synthesized gemini surfactants are higher.…”

“…The CMC/ C 20 ratio measures the tendency for micelle formation relative to air/water interface adsorption . These p C 20 values in Table , which are higher than those of some gemini surfactants, ,,, indicate that these synthesized gemini quaternary ammonium surfactants have comparatively higher efficiency in reducing the surface tension. Furthermore, the increasing trend of p C 20 suggests the efficiency increases with increasing chain length.…”