2.5. DPH fluorescence assay

DPH (1,6-diphenyl-1,3,5-hexatriene) fluorescence was measured to elucidate peptide interaction with different micelles i.e. SDS and DPC ^{[18], [19]}. Initially, a stock solution of DPH was prepared in acetone and subsequently diluted into the working buffer (10 mM phosphate buffer, pH 7.2) to a final concentration of ~ 18 μM. Next, fixed concentration of micelles, e.g., 5 mM for DPC or 20 mM for SDS was added to the above solution and initial fluorescence intensity (F₀) was recorded with an excitation wavelength of 358 nm and emission profile in the range of 400 to 600 nm with a 5-nm slit width. Increasing concentrations of TK9 peptide (0–50 μM) were added separately to each system containing DPH and micelle, following which the fluorescence intensity (F) was measured. Finally, relative DPH fluorescence intensity enhancement (ΔF) was calculated using the following equation: