影响微乳形成因素的研究

[目的]考察不同因素对微乳形成的影响。[方法]选择聚氧乙烯山梨醇脂肪酸酯-80(Tween 80)、聚氧乙烯氢化蓖麻油(CremopherRH40)、聚氧乙烯蓖麻油(Cremopher EL35)、聚乙二醇-8-甘油辛酸/癸酸酯(Labrasol)为乳化剂,1,2-丙二醇、Transcutol为助乳化剂,麻油、辛癸酸甘油酯、肉豆蔻酸异丙酯为油相,改变乳化剂和助乳化剂不同质量比(Km),制备微乳,通过绘制相图考察形成微乳区面积的大小。[结果]以Cremopher RH40为乳化剂,乙二醇单乙基醚(Transcutol)为助乳化剂,Km为3∶1时,不同的油形成微乳的能力:辛癸酸甘油酯>肉豆蔻酸异丙酯>麻油;以辛癸酸甘油酯为油相,Transcutol为助乳化剂,Km为3∶1时,不同表面活性剂形成微乳的能力:CremopherRH40、Cremopher EL35>Tween 80>Labrasol;以辛癸酸甘油酯为油相,Cremopher RH40为乳化剂,不同助表面活性剂形成微乳的能力:1,2-丙二醇>Transcutol。[结论]油相分子大小及油相含量、乳化剂、助乳化剂种类及含量均对微乳的形成有影响。     

Fluorescence Reporting of Binding Interactions of Target Molecules with Core–Shell‐Type Cortisol‐Imprinted Polymer Particles Using Environmentally Responsible Fluorescent‐Labeled Cortisol

Core–shell‐type molecularly imprinted polymer particles (MIP‐NPs) bearing specific binding cavities for cortisol in their shell layers by two‐step emulsifier‐free emulsion polymerizations are synthesized, where both the strategies of semicovalent molecular imprinting and noncovalent molecular imprinting are concurrently performed using methacryloyl cortisol and itaconic acid as a template molecule and a functional monomer, respectively. Newly designed fluorescent reporter molecules, dansyl‐labeled cortisol, to investigate the binding capability of MIP‐NPs toward cortisol by fluorescence measurements are developed. The binding rate constant (k_a) and affinity constant (K_a) of MIP‐NPs toward cortisol are successfully estimated by curve fitting for fluorescence spectral shift. The k_a value of MIP‐NPs is 1.8 times larger than that of reference MIP‐NPs prepared using only methacryloyl cortisol without itaconic acid (semicovalent imprinting), indicating that the concurrent demonstration of both the semicovalent imprinting and noncovalent imprinting processes is effective for constructing high affinity binding cavities for cortisol.