Complexation of cationic-neutral block polyelectrolyte with insulin and in vitro release studies

Abstract

Insulin (INS) was incorporated into complexes with the block polyelectrolyte quaternized poly[3,5-bis(dimethylaminomethylene)hydroxystyrene]-b-poly(ethylene oxide) (QNPHOSEO), which is a cationic-neutral block polyelectrolyte. Light scattering techniques are used in order to examine the size, the size distribution and the ζ-potential of the nanocarriers in aqueous and biological media, which are found to depend on the ratio of the components and the physicochemical parameters during and after complex preparation. Circular dichroism and infrared spectroscopy, employed to investigate the structure of the complexed INS, show no alteration of protein structure after complexation. In vitro release profiles of the entrapped protein are found to depend on the ratio of the components and the solution conditions used during preparation of the complexes.

Complex coacervate‐based materials for biomedicine

“…Fortunately, coacervation is a relatively gentle method for encapsulation that maintains proteins in an aqueous environment. Typical reports have shown minimal evidence for adverse effects of coacervation on protein structure …”

“…However, for many biomedical applications, changes in pH associated with cellular uptake via endocytosis can be used to trigger disassembly of the coacervate‐based delivery vehicle. Alternatively, more stable interactions can be utilized for controlled release systems …”

“…The scope of coacervation has expanded from proteins and polysaccharides to include polynucleotides, synthetic polymers, surfactants, nanoparticles, and other hierarchical assemblies . Furthermore, the utility of coacervates has extended into fields such as adhesives, drug delivery, nano/bioreactors, and cellular biology …”

“…C omplex coacervation is an associative, liquidliquid phase separation phenomenon [1][2][3][4][5][6][7][8][9][10][11][12] that is driven by an initial electrostatic attraction between oppositely charged macroions, [1][2][3][4][5][13][14][15][16][17][18][19] followed by the entropic gains associated with the release of small, bound counterions and the restructuring of water molecules. [1][2][3]13 The original work by Bungenberg de Jong and Kruyt focused on biomacromolecular systems of proteins and polysaccharides.…”

“…[21][22][23][24][25][26] The scope of coacervation has expanded from proteins and polysaccharides to include polynucleotides, 7,8,[27][28][29][30] synthetic polymers, 31-37 surfactants, 38-45 nanoparticles, 46,47 and other hierarchical assemblies. [48][49][50][51][52][53][54][55] Furthermore, the utility of coacervates has extended into fields such as adhesives, 9,[56][57][58][59][60][61][62][63][64][65][66][67][68][69][70] drug delivery, 4,7,8,[16][17][18][19]28,32,34,[71][72][73][74][75][76][77][78][79]…”