• Andersson, Toni
• Tenhu, Heikki
• Aseyev, Vladimir O.

Abstract

Intermol. complexes of genomic polydisperse DNA with synthetic polycations have been studied.Two cationic polymers have been used, a homopolymer poly(methacryl oxyethyl trimethylammonium chloride) (PMOTAC) and its analog grafted with poly(oxyethylene).The amt. of poly(oxyethylene) grafts in the copolymer was 15 mol % and Mw of the graft was 200 g/mol.Salmon DNA (sodium salt) was used.The av. mol. wt. (Mw) of DNA was 10.4 × 106 g/mol.Cond., pH, and dynamic light scattering studies were used to characterize the complexes.The size and shape of the polyelectrolyte complex particles have been studied as a function of the cation-to-anion ratio in aq. solns. of varying ionic strengths.The polyelectrolyte complexes have extremely narrow size distributions taking into account the polydispersity of the polyelectrolytes studied.The poly(oxyethylene) grafts on PMOTAC promote the formation of small colloidally stabile complex particles.Addn. of salt shifts the macroscopic phase sepn. toward lower polycation content; i.e., complexes partly phase sep. with the mixing ratios far from 1:1.Further addn. of salt to the turbid, partly phase sepd. soln. results in the dissocn. of complexes and the polycation and DNA dissolve as individual chains. [on SciFinder(R)]

Topics

• phase
• strength
• Sodium
• copolymer
• homopolymer
• polydispersity
• dynamic light scattering