Roy Tanmoy, Padhi Swarupanjali
Department of Pharmaceutics, Noida Institute of Engineering and Technology (Pharmacy Institute), Gautam Buddha Nagar, Greater Noida, Uttar Pradesh, 201306, India.
J Fluoresc. 2025 Feb 19. doi: 10.1007/s10895-025-04209-x.
Micelles are small spherical structures formed by one or a combination of amphiphilic structures known as surfactants. Surfactants are amphiphilic molecules with both hydrophilic and hydrophobic regions and can self-assemble into micelles above the critical micelle concentration, with the hydrophobic tails oriented inwards and hydrophilic head outwards. In this review article, critical micelle concentration determination using the fluorescence spectroscopy technique is described for both single and mixed micellar systems with the preparation of samples, working principle, and also about theoretical aspects. Fluorescence measurements using direct i.e. intrinsic fluorescence of surfactant molecule and indirect i.e. using extrinsic fluorescence probes have been discussed. Fluorescence spectroscopy offers a sensitive and valid approach for the characterization of surfactant behaviors in aqueous solutions. Various fluorescence parameters are measured at specific wavelengths with an increase in surfactant concentration and a plot is generated from which the critical micelle concentration is determined. Furthermore, the calculation of critical packing parameter is also described which gives an idea about the geometrical arrangement of the surfactant molecules in a micellar structure. This value also provides valuable insights into the micelle's shape and structure. In conclusion, the effectiveness of the fluorescence spectroscopy technique in determining the critical micelle concentration and the critical packing parameter is described in detail in this review article.
胶束是由一种或多种被称为表面活性剂的两亲结构形成的小球形结构。表面活性剂是具有亲水和疏水区域的两亲分子，在临界胶束浓度以上可自组装成胶束，疏水尾部向内，亲水头部向外。在这篇综述文章中，描述了使用荧光光谱技术测定单胶束体系和混合胶束体系的临界胶束浓度，包括样品制备、工作原理以及理论方面。讨论了使用直接即表面活性剂分子的固有荧光和间接即使用外部荧光探针的荧光测量方法。荧光光谱法为表征表面活性剂在水溶液中的行为提供了一种灵敏且有效的方法。随着表面活性剂浓度的增加，在特定波长下测量各种荧光参数，并生成一个图，从中确定临界胶束浓度。此外，还描述了临界堆积参数的计算，它能让人了解表面活性剂分子在胶束结构中的几何排列。该值还为胶束的形状和结构提供了有价值的见解。总之，这篇综述文章详细描述了荧光光谱技术在测定临界胶束浓度和临界堆积参数方面的有效性。
