Stewart Assay for determing concentration of lipids

 Stewart, J. C. Colorimetric Determination of Phospholipids with Ammonium Ferrothiocyanate. Anal Biochem 1980, 104 (1), 10–14. https://doi.org/10.1016/0003-2697(80)90269-9.

This article describes a very cheap and easy approach to quantify the concentration of lipids in liposomes. By forming a colored complex that can be quantify by UV/vis spectroscopy.  The colorimetric assay outlined in the article presents a potential alternative or complementary approach to existing methods for detecting and quantifying phospholipids, possibly offering advantages in terms of simplicity and efficiency for biochemical analysis.