Construction of pseudo-ternary phase diagrams based on orthogonal design at 25 °C.
(A) Test No.1: limonene (oil), Smix (Tween 80/Transcutol HP = 2:1, w/w) and
water; (B) test No.2: limonene (oil), Smix (Tween 80/PEG 400 = 3:2, w/w)
and water; (C) test No.3: limonene (oil), Smix (Tween 80/glycerol = 3:1,
w/w) and water; (D) EO (oil), Smix (Tween 80/Transcutol HP = 3:2, w/w) and
water; (E) EO (oil), Smix (Tween 80/PEG 400 = 3:1, w/w) and water; (F) EO
(oil), Smix (Tween 80/glycerol = 2:1, w/w) and water; (G) OA (oil),
Smix (Tween 80/Transcutol HP = 3:1, w/w) and water; (H) OA (oil),
Smix (Tween 80/PEG 400 = 2:1, w/w) and water; (I) OA (oil),
Smix (Tween 80/glycerol = 3:2, w/w) and water. The region of blank
microemulsion (without lycopene) is labeled ME. Limonene:
(R)-(+)-limonene; EO: ethyl oleate; OA: oleic acid; Smix:
the surfactant and co-surfactant mixture.