A series of novel di-hydroxyl-sulfate-betaine-type zwitterionic gemini surfactants of 1,2-bis[N-ethyl-N-(2-hydroxyl-3-sulfopropyl)-alkylammonium] alkyl betaines (DBA(s-n), where s and n represent the spacer length of 2, 4 and 6 and the hydrocarbon chain length of 8, 12, 14, 16 and 18, respectively) were synthesized by reacting alkylamine with sodium 3-chloro-2-hydroxypropanesulfonate (the alternative sulphonated agent), followed by the reactions with a omega-dibromoalkyl and then ethyl bromide. Their adsorption and aggregation properties were investigated by means of equilibrium surface tension, dynamic light-scattering (DLS) and transmission electron microscopy (TEM). DBA(s-n) gemini surfactants showed excellent surface activities and packed tightly at the interface. For example, the minimum CMC value for DBA(s-n) series was of the order of 10(-5)M and the surface tension of water can be decreased as low as 22.2 mN/m. It was also found that the aggregates of DBA(s-n) solutions were significantly dependent on their hydrocarbon chain lengths. The aggregates changed from vesicles to entangled fiber-like micelles as the chain length increased from dodecyl to tetradecyl. (C) 2013 Elsevier B.V. All rights reserved.