Table 2: Calculated hydrophilic-lipophilic balance (HLB) values of the nonionic surfactants in the single and binary surfactant systems.

Surfactant/mixed surfactantHLB number

Tween 8015.00
Span 804.30
Tween 80 : Span 80 (9 : 1)13.93
Tween 80 : Span 80 (8 : 2)12.86
Tween 80 : Span 80 (7 : 3)11.79