以二氨基蓝3R(DAB)和玫瑰红B(RB)两种离子型有机物为探针,研究了其与体外单层磷脂膜(SPM)和大肠杆菌之间的相互作用,结合作用符合Langmuir和Temkin等温化学吸附方程.考察了pH、离子强度和温度对吸附作用的影响,分析了DAB,RB与SPM和细胞的结合形式、结合键和结合位置.结果表明,DAB,RB与SPM和细胞外膜有强烈的单分子层化学吸附,是自发的放热反应,主要通过电荷对吸引、氢键等非共价键结合在SPM和细胞外表面,且绝大部分DAB,RB积累、滞留在细胞膜壁上.混合作用时,两种有机物存在竞争吸附结合现象。
The binding of ionic organic compounds, anionic diamine blue 3R (DAB) and cationic rhodamine B (RB) to in vitro single phospholipids membrane (SPM) and Escherichia coli (E. coli) strains was investigated. The interactions correspond to the Langmuir and Temkin adsorption isotherm in only monolayers. The influence of ionic strength, pH and temperature on the adsorption were examined and analyzed. The binding force, type and interaction sites of DAB and RB were determined and identified. The interaction of DAB and RB with SPM and the cells are exothermal and idiopathic, which contained the union of non-covalent bonds, such as electrostatic bond, hydrogen bond and van der Waals force. Moreover, most of- DAB and RB were accumulated on the excellular membrane and walls, to hardly enter the cytoplasm. Besides, the adsorption competition was found when both DAB and RB existed simultaneously.