A new type of cationic surfactant prepared by surface modification on sucrose carbon dots via an entirely green approach and the inhibition on growth of E. coli and S. aureus

Sucrose was renewable resource which was a raw material for preparing carbon dots (CDs) since it was readily to be carbonized. Chemical modification could realize a tremendous change of the performance of the CDs. A novel technique of preparing a new type of cationic surfactant derived from sucrose CDs (SCDs) was described herein in detail. Firstly, SCDs were prepared via a hydrothermal treatment of 180° on the mixture of 1.0 g aqueous sucrose solution and 200 μL hydrogen peroxide for 2.0 h. Then SCDs were modified chemically by virtue of reflux heating on mixture of SCDs and n-dodecylamine in aqueous medium for realizing chemical bonding between hydrophobic hydrocarbon chain in n-dodecylamine and SCDs (represented with SCDs-C12). SCDs-C12 declined surface tension of water from 72.0 to 32.9 mN m⁻¹ which was comparable to several traditional surfactants or novel cationic surfactants. Moreover, any organic solvent was never used in the whole procedure. Zeta potential measurement indicated SCDs-C12 was positive charged which declared SCDs-C12 belonged to cationic surfactant. Antibiosis experiments demonstrated SCDs-C12 performed wonderfully in inhibiting the growth of E. coli and S. aureus. Thus we provided a green chemical approach of preparing a new type of cationic surfactant with inexpensive raw material.