Adsorptive property of Cu²⁺-loaded montmorillonite clays for Escherichia coli K₈₈in vitro

• Published in: Journal of environmental sciences (China) Vol. 23; no. 11; pp. 1808 - 1815
• Main Authors: Guo, Tong, Cao, Shoujun, Su, Rui, Li, Zhiqiang, Hu, Ping, Xu, Zirong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2011
• Subjects: adsorption; bacteria; cell walls; electrostatic interactions; Escherichia coli; ionic strength; montmorillonite; scanning electron microscopy; temperature; zeta potential
• ISSN: 1001-0742; 1878-7320
• DOI: 10.1016/S1001-0742(10)60651-1

The adsorption properties of Cu²⁺-loaded montmorillonite clays (MMT-Cu) for Escherichia coli K₈₈ as a function of time, bacteria concentrations, pH, ionic strength and temperature were investigated. The results showed that the bacteria adsorption onto MMT-Cu surface reached equilibrium after 90 min. The percentages of E. coli K₈₈ adsorbed onto the surfaces of MMT-Cu and montmorillonite clays (MMT) at equilibrium were 88.9% and 56.5%, respectively. Scanning electron microscopy revealed that a lot of E. coli K₈₈ adhered to the surface of MMT-Cu. The zeta potential of MMT-Cu was relatively high as compared to that of MMT. The adsorptive ability of MMT-Cu for E. coli K₈₈ was higher than that of MMT (P < 0.05). Moreover, pH, ionic strength and temperature produced a strong influence on the extent of E. coli K₈₈ adsorption to surface of MMT-Cu and MMT. The mechanism of adsorption of E. coli onto MMT-Cu may involve electrostatic attraction and physiochemical properties of bacterial cell walls and minerals surfaces.