Effect of pH on the structure and drug release profiles of layer-by-layer assembled films containing polyelectrolyte, micelles, and graphene oxide

Abstract

Layer by layer (lbl) assembled multilayer thin films are used in drug delivery systems with attractive advantages such as unlimited selection of building blocks and free modification of the film structure. In this paper, we report the fundamental properties of lbl films constructed from different substances such as PS-b-PAA amphiphilic block copolymer micelles (BCM) as nano-sized drug vehicles, 2D-shaped graphene oxide (GO), and branched polyethylenimine (bPEI). These films were fabricated by successive lbl assembly as a result of electrostatic interactions between the carboxyl group of BCM and amine group of functionalized GO or bPEI under various pH conditions. We also compared the thickness, roughness, morphology and degree of adsorption of the (bPEI/BCM) films to those in the (GO/BCM) films. The results showed significant difference because of the distinct pH dependence of each material. In addition, drug release rates of the GO/BCM film were more rapid those of the (bPEI/BCM) film in pH 7.4 and pH 2 PBS buffer solutions. In (bPEI/BCM/GO/BCM) film, the inserted GO layers into bPEI/BCM multilayer induced rapid drug release. We believe that these materials & pH dependent film properties allow developments in the control of coating techniques for biological and biomedical applications.

Toxicity of graphene-family nanoparticles: a general review of the origins and mechanisms

“…GO is one of the most vital chemical graphene derivatives of the graphene-family nanomaterials (GFNs), which attracts increasing attention for its potential biomedical applications. Graphene-based materials usually have sizes ranging from several to hundreds of nanometer and are 1-10 nm thick [8, 9], which is also the definition of ‘nanoparticles’ or ‘nanomaterials’. Due to their exceptional physical and chemical properties, graphene materials have been widely used in various fields, including energy storage; nanoelectronic devices; batteries [10–12]; and biomedical applications, such as antibacterials [13, 14], biosensors [15–18], cell imaging [19, 20], drug delivery [8, 21, 22], and tissue engineering [23–25].…”

Organic-inorganic hybrid layer-by-layer electrostatic self-assembled film of cationic dye Methylene Blue and a clay mineral: Spectroscopic and Atomic Force microscopic investigations

“…The resultant transition dipole moment will lead to the appearance of more broadened and diffused absorption spectral profile for higher order aggregates. The absorption spectroscopic results of MB aqueous solution with respect to their different ionic form for the pH range studied (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13) here is also summarized in Table 1. Fig.…”

“…However, this LbL self-assembly process is not only restricted to simple polyelectrolytes rather extended to cover wide diversity of materials such as many biological molecules, inorganic nanoparticles and semiconductors, smectites (clay mineral) etc. to organize their molecular assemblies with various tailored properties [8][9][10][11] for technological applications [12,13]. This simple method is also environment-friendly and potentially economic method to engineer the molecular arrangement onto a solid support.…”

Biocompatible disulphide cross-linked sodium alginate derivative nanoparticles for oral colon-targeted drug delivery

“…Furthermore, the presence of polyelectrolyte layers in P3DL/PAH/PSSCMA resulted in slow drug release. The layers became an obstacle, and they sustained the release of PCX from rapid burst [36,[40][41][42] due to the strong electrostatic attraction between the oppositely charged polyelectrolytes thus decrease the ability to release the drug [36,43].…”