Water solutions for Brij 58 and Brij S20 (with concentrations ranging from 0.001 to 0.1 mM) were prepared separately at 25 ℃. Eosin Y dye (0.01 mM) was added to each Brij solution as per the standard method of dye micellization technique . A UV-VIS spectrophotometer (Model: JASCO, Japan) was used to measure the samples' absorbance at 540 nm, which represented the absorbance of the dye in the Brij micelles. At 515 nm, the highest absorbance of unattached eosin molecules in liquid was found. The absorbance vs. Brij quantity curve (Figure (A) and (B)) was used for the CMC point identification. For the pH stability analysis of the micelles at their individual CMC the absorbance at 540 nm was also checked at pH levels of 1.5, 3, 5, 7, and 9 up to 24 h at 25 ℃. As DT is a heat labile compound higher temperatures were avoided.