Wangsakan A, Chinachoti P, McClements D J
Biopolymers and Colloids Research Group, Department of Food Science, University of Massachusetts, Amherst, Massachusetts 01003, USA.
J Agric Food Chem. 2001 Oct;49(10):5039-45. doi: 10.1021/jf0103471.
Interactions between maltodextrin (DE = 10) and an anionic surfactant (sodium dodecyl sulfate, SDS) were studied in a buffer solution (pH 7.0, 10 mM NaCl, 20 mM Trizma, 30.0 degrees C) using isothermal titration calorimetry (ITC), surface tension, differential scanning calorimetry (DSC), and turbidity techniques. ITC measurements indicated that the binding of SDS to maltodextrin was exothermic and that, on average, one SDS monomer bound per 24 glucose units of maltodextrin at saturation. Surface tension measurements indicated that there was a critical surfactant concentration ( approximately 0.05 mM SDS) below which surfactant and maltodextrin did not interact and that the amount of surfactant bound to the maltodextrin above this concentration increased with increasing maltodextrin concentration. Turbidity measurements indicated that the solutions remained transparent at all maltodextrin (0-1 wt %) and SDS (0-20 mM) concentrations studied, which suggested that phase separation did not occur. DSC measurements indicated that no phase transitions occurred between 10 and 110 degrees C for maltodextrin solutions (0.5 wt %) in the presence or absence of surfactant. A phase diagram was developed to describe the interactions between SDS and maltodextrin.
在缓冲溶液（pH 7.0、10 mM氯化钠、20 mM三羟甲基氨基甲烷、30.0℃）中，使用等温滴定量热法（ITC）、表面张力、差示扫描量热法（DSC）和浊度技术研究了麦芽糊精（DE = 10）与阴离子表面活性剂（十二烷基硫酸钠，SDS）之间的相互作用。ITC测量表明，SDS与麦芽糊精的结合是放热的，并且在饱和时，平均每24个麦芽糊精葡萄糖单位结合一个SDS单体。表面张力测量表明，存在一个临界表面活性剂浓度（约0.05 mM SDS），低于该浓度时表面活性剂和麦芽糊精不相互作用，且高于该浓度时与麦芽糊精结合的表面活性剂数量随麦芽糊精浓度的增加而增加。浊度测量表明，在所研究的所有麦芽糊精（0 - 1 wt%）和SDS（0 - 20 mM）浓度下，溶液均保持透明，这表明未发生相分离。DSC测量表明，在有或没有表面活性剂的情况下，麦芽糊精溶液（0.5 wt%）在10至110℃之间均未发生相变。绘制了相图以描述SDS与麦芽糊精之间的相互作用。
