Entrapment of a Weak Polyanion and H+/Na+ Exchange in Confined Polyelectrolyte Microcapsules

An approach for the entrapment of a polyanion by polyelectrolyte microcapsules is reported. It is based on a reversal changing of microcapsule wall permeability from neutral to basic pH. Polyelectrolyte microcapsules were templated on latex (polystyrene) particles by the layer-by-layer adsorption of oppositely charged polymers of sodium poly(styrene sulfonate) and poly(allylamine hydrochloride), followed by core removal using tetrahydrofuran. In alkaline conditions, the microcapsules swell and become permeable for polymers. During encapsulation, the addition of salt ions increases the amount of the polymer encapsulated and contributes to its protonation because of redistribution of H+ ions across a semipermeable microcapsule wall. The redistribution of small ions across the microcapsule wall was tuned by adding salt according to the Donnan equilibrium and was characterized by H+ sensitive dyes.

[1]  M. Cowman,et al.  Poly(N-isopropylacrylamide-co-1-vinylimidazole) Hydrogel Nanoparticles Prepared and Hydrophobically Modified in Liposome Reactors: Atomic Force Microscopy and Dynamic Light Scattering Study , 2003 .

[2]  Jia-cong Shen,et al.  Enhanced biomacromolecule encapsulation by swelling and shrinking procedures. , 2004, Chemphyschem : a European journal of chemical physics and physical chemistry.

[3]  D. M. Lynn,et al.  Tunable drug release from hydrolytically degradable layer-by-layer thin films. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[4]  H. Möhwald,et al.  Hollow polyelectrolyte shells: Exclusion of polymers and Donnan equilibrium. , 1999 .

[5]  H. Möhwald,et al.  Controlled Permeability of Polyelectrolyte Capsules via Defined Annealing , 2002 .

[6]  H. Möhwald,et al.  Polyelectrolyte multilayer capsule permeability control , 2002 .

[7]  G. Sukhorukov,et al.  pH-responsive properties of hollow polyelectrolyte microcapsules templated on various cores. , 2004, Langmuir : the ACS journal of surfaces and colloids.

[8]  G. Sukhorukov,et al.  Model system for controlled protein release: pH-sensitive polyelectrolyte microparticles , 2003 .

[9]  G. Sukhorukov,et al.  Defined Picogram Dose Inclusion and Release of Macromolecules using Polyelectrolyte Microcapsules , 2005 .

[10]  Andreas Voigt,et al.  pH-controlled macromolecule encapsulation in and release from polyelectrolyte multilayer nanocapsules. , 2001 .

[11]  G. Sukhorukov,et al.  Base-acid equilibria in polyelectrolyte systems: From weak polyelectrolytes to interpolyelectrolyte complexes and multilayered polyelectrolyte shells , 2003 .

[12]  J Hartmann,et al.  Microencapsulation by means of step-wise adsorption of polyelectrolytes. , 2000, Journal of microencapsulation.

[13]  Helmuth Möhwald,et al.  Novel Hollow Polymer Shells by Colloid-Templated Assembly of Polyelectrolytes. , 1998, Angewandte Chemie.

[14]  Michael F. Rubner,et al.  Influence of the Degree of Ionization on Weak Polyelectrolyte Multilayer Assembly , 2005 .

[15]  H. Möhwald,et al.  The decomposition process of melamine formaldehyde cores: The key step in the fabrication of ultrathin polyelectrolyte multilayer capsules. , 2001 .

[16]  K. R. Rogan.  The variations of the configurational and solvency properties of low molecular weight sodium polyacrylate with ionic strength , 1995 .

[17]  Lars Dähne,et al.  Tailor-made polyelectrolyte microcapsules: from multilayers to smart containers. , 2004, Angewandte Chemie.

[18]  H. Möhwald,et al.  Physical chemistry of encapsulation and release , 2004 .

[19]  G. Sukhorukov,et al.  Polyelectrolyte multilayer capsules as vehicles with tunable permeability. , 2004, Advances in colloid and interface science.