Abstract：
Gum Arabic underwent enzymatic modification with curcumin oxidation products, prompting self-assembly in water at lower concentrations than native gum Arabic, which was fully soluble. The resulting particles displayed a narrow size distribution, suggestive of a micellization mechanism akin to Critical Micellization Concentration (CMC) in surfactants or Critical Aggregation Concentration (CAC) in polymers. Accurately determining CAC is vital for utilizing polymers in molecule encapsulation, but precise measurement is challenging, requiring multiple techniques. Initially, CAC was probed via turbidity measurements, dynamic light scattering (DLS), and isothermal calorimetric titration (ITC), yielding a range of 0.0015 to 0.01 %. Micro-scale thermophoresis (MST) was then employed for the first time to define CAC more precisely, facilitated by the intrinsic fluorescence of modified gum Arabic. Using MST, CAC was pinpointed at 0.001 % (w/v), a novel approach. Furthermore, MST revealed a low EC50 value of 0.007 % (w/t) for self-assembly, signifying uniformity among GAC sub-units and assembly stability upon dilution.
摘要：
阿拉伯树胶用姜黄素氧化产物进行了酶促修饰，促使在水中以低于天然阿拉伯树胶的浓度进行自组装，是完全可溶的。得到的颗粒显示出窄的尺寸分布，提示胶束化机理类似于表面活性剂中的临界胶束化浓度（CMC）或聚合物中的临界聚集浓度（CAC）。准确测定CAC对于在分子封装中利用聚合物至关重要，但是精确测量是具有挑战性的，需要多种技术。最初，通过浊度测量探测CAC，动态光散射(DLS),和等温量热滴定(ITC)，产量范围为0.0015至0.01%。然后首次采用微尺度热泳（MST）更精确地定义CAC，由改性阿拉伯树胶的内在荧光促进。使用MST，CAC被确定为0.001%(w/v)，一种新颖的方法。此外，MST显示自组装的低EC50值为0.007％（w/t），表示GAC子单元之间的均匀性和稀释时的组装稳定性。
