title: [Adsorption and desorption of Bt toxin on three kinds of minerals].
abstract: This paper studied the characteristics of the adsorption and desorption of Bt (Bacillus thuringiensis) toxin on goethite, kaolinite, and silica. The results showed that in phosphate buffer (pH 8), the adsorption isotherms of Bt toxin on the test minerals followed Langmuir equation (R2 >0. 9661), and the adsorbed amounts were in the order of goethite > kaolinite > silica. The Bt toxin was easily adsorbed on the minerals, and the adsorption could reach equilibrium after 1 hour. Within the range of pH 6-8, the amounts of Bt toxin adsorbed on goethite, kaolinite and silica decreased with increasing pH; in the range of 10 degrees C-50 degrees C, the amounts of the toxin adsorbed on goethite and silica decreased by 8.39% and 47.06%, respectively, while that on kaolinite increased slightly (5.91%). The infrared absorption spectrum showed that there was only a minor alteration of Bt toxin after adsorption. The toxin adsorbed on the minerals was not easily desorbed by deionised water, with the desorption rate ranged from 28.48% to 42.04% after three times washing.
authors.affiliation: Key Laboratory of Refractories and Ceramics of Hubei Province, Wuhan University of Science and Technology, Wuhan 430081, China. zhouxueyongts@163.com
authors.forename: Xue-Yong
authors.initials: XY
authors.lastname: Zhou
authors.forename: Jian-Bao
authors.initials: JB
authors.lastname: Gao
authors.forename: Peng
authors.initials: P
authors.lastname: Cai
authors.forename: Qiao-Yun
authors.initials: QY
authors.lastname: Huang
mesh_terms: D000327:Adsorption; D001413:Bacillus thuringiensis / Q000737:chemistry; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000737:chemistry*; D001427:Bacterial Toxins / Q000737:chemistry*; D004731:Endotoxins / Q000737:chemistry*; D006460:Hemolysin Proteins / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D058085:Iron Compounds / Q000737:chemistry; D007616:Kaolin / Q000737:chemistry; D007700:Kinetics; D008903:Minerals / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D013055:Spectrophotometry, Infrared
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D058085:Iron Compounds; D008903:Minerals; C030956:insecticidal crystal protein, Bacillus Thuringiensis; C094886:goethite; D007616:Kaolin; D012822:Silicon Dioxide