Encapsulation of Curcumin in Polystyrene-Based Nanoparticles—Drug Loading Capacity and Cytotoxicity

Abstract

Nanoparticles made of amphiphilic block copolymers are commonly used in the preparation of nano-sized drug delivery systems. Poly(styrene)– block – poly(acrylic acid) (PS–PAA) copolymers have been proposed for drug delivery purposes; however, the drug loading capacity and cytotoxicity of PS–PAA nanoparticles are still not fully recognized. Herein, we investigated the accumulation of a model hydrophobic drug, curcumin, and its spatial distribution inside the PS–PAA nanoparticles. Experimental methods and atomistic molecular dynamics simulations were used to understand the molecular structure of the PS core and how curcumin molecules interact and organize within the PS matrix. The hydrophobic core of the PS–PAA nanoparticles consists of adhering individually coiled polymeric chains and is compact enough to prevent post-incorporation of curcumin. However, the drug has a good affinity for the PS matrix and can be efficiently enclosed in the PS–PAA nanoparticles at the formation stage. At low concentrations, curcumin is evenly distributed in the PS core, while its aggregates were observed above ca. 2 wt %. The nanoparticles were found to have relatively low cytotoxicity to human skin fibroblasts, and the presence of curcumin further increased their biocompatibility. Our work provides a detailed description of the interactions between a hydrophobic drug and PS–PAA nanoparticles and information on the biocompatibility of these anionic nanostructures which may be relevant to the development of amphiphilic copolymer-based drug delivery systems.

Molecular Dynamics Simulations of Adsorption of SARS-CoV-2 Spike Protein on Polystyrene Surface

“…This force field has been previously used and verified for MD simulation of polystyrene–bioactive ligand complexes. 33 The systems were placed in the center of the cubic box, and the minimum distance between the system and the box boundaries was set to 1.0 nm. The lowest three layers of the polystyrene slab were geometrically frozen during the simulations to approximate a realistic polymeric slab configuration.…”

“…The CHARMM36 atom types and their charges used for polystyrene are presented in Figure S2 and Table S1. This force field has been previously used and verified for MD simulation of polystyrene–bioactive ligand complexes . The systems were placed in the center of the cubic box, and the minimum distance between the system and the box boundaries was set to 1.0 nm.…”

HNT-Cellulose based Nano-Composite and Applications

“…Further, hydrogels are loaded with curcumin through physical adsorption [37]. The cytotoxicity of curcumin-loaded hydrogels is explored on cancer cells and has found prominent applications such as drug delivery in cancer and anti-inflammatory wound dressing [38].…”

Polymer-Based Nanosystems—A Versatile Delivery Approach

“…PSNPs are biocompatible, do not induce inflammation, bind to a range of antigens due to their easily modifiable surface, and generate CD8+T cell responses specific to the delivered peptides [75,148]. Moreover, PS can be associated with other polymers to create amphiphilic block copolymers that are stable in aqueous media, while also being able to encapsulate hydrophobic bioactive substances [149].…”