Novaflux Inc., 1 Wall Street, Princeton, NJ, 08540, United States; Advanced BioDevices LLC., 1 Wall Street, Princeton, NJ, 08540, United States.
Dairy Goat Co-operative (N.Z.) Limited, 18 Gallagher Drive, PO Box 1398, Hamilton 3240, New Zealand.
Adv Colloid Interface Sci. 2021 Apr;290:102392. doi: 10.1016/j.cis.2021.102392. Epub 2021 Mar 5.
Phospholipids are the main constituents of cell membranes and act as natural stabilizers of milk fat globules. Phospholipids are used in a wide range of applications, e.g. as emulsifiers in cosmetic, pharmaceutical and food products. While processed emulsion droplets are usually stabilized by a monolayer of phospholipids, cell membranes have a phospholipid bilayer structure and milk fat globules are stabilized by a complex phospholipid trilayer membrane. Despite the broad relevance of phospholipids, there are still many scientific challenges in understanding how their behavior at the fluid-fluid interface affects microstructure, stability, and physico-chemical properties of natural and industrial products. Most of these challenges arise from the experimental difficulties related to the investigation of the molecular arrangement of phospholipids in situ at the fluid-fluid interface and the quantification of their partitioning between the bulk phase and the interface, both under static and flow conditions. This task is further complicated by the presence of other surface-active components, such as proteins, that can interact with phospholipids and compete for space at the interface. Here, we review the methodologies available from the literature to detect and quantify phospholipids, focusing on oil-water interfaces, and highlight current limitations and future perspectives.
磷脂是细胞膜的主要成分，作为牛奶脂肪球的天然稳定剂。磷脂广泛应用于化妆品、制药和食品等领域，可用作乳化剂。虽然加工后的乳液液滴通常由单层磷脂稳定，但细胞膜具有磷脂双层结构，而牛奶脂肪球则由复杂的磷脂三层膜稳定。尽管磷脂具有广泛的相关性，但在理解其在流体-流体界面的行为如何影响天然和工业产品的微观结构、稳定性和物理化学性质方面仍存在许多科学挑战。这些挑战大多源于在静态和流动条件下原位研究磷脂在流体-流体界面的分子排列以及定量它们在本体相与界面之间分配的实验困难。当存在其他表面活性剂成分（如蛋白质）时，这一任务会更加复杂，因为这些成分会与磷脂相互作用并争夺界面空间。本文综述了文献中可用于检测和定量油-水界面磷脂的方法，并重点介绍了当前的局限性和未来的展望。
