Caracterizacao de novos sistemas para particao bifasica aquosa de biomoleculas

Aqueous two phase partition explores the possibility of solutions of two polymers or one polymer and one salt separating into two immiscible aqueous phases, when certain critical concentrations are exceeded. Each one of these aqueous phases is more concentrated in one of the phase forming chemicals. Both exhibit a high water content, usually more than 80% (w/w) and in some cases as much as 95%. Due to this high water content, these biphasic systems provide a gentle environment for molecules and particles with biological activity. The main subject of this thesis is the characterisation of new aqueous two phase systems based on crude polymers as phase forming polymers, since the cost of the phase forming polymers is the main drawback on the large scale application of aqueous two phase partition. Aqueous two phase systems based on crude polymers are less expensive and so the applicability of this technique can be increased. The presented work is performed exclusively on polymer polymer two phase systems. Polyethylene glycol is used as one of the two phase forming polymers in all tested systems and as the other polymer a crude guar gum are tested..Available from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1249-074 Lisboa, Portugal / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga