Systematic design and application of unimolecular star-like block copolymer micelles: a coarse-grained simulation study

Abstract

Unimolecular polymeric micelles have several features, such as thermodynamic stability, small particle size, biocompatibility, and the ability to internalize hydrophobic molecules. These micelles have recently attracted significant attention in various applications, such as nano-reactors, catalysis, and drug delivery. However, few attempts have explored the formation mechanisms and conditions of unimolecular micelles due to limited experimental techniques. In this study, a unimolecular micelle system formed from β-cyclodextrin-graft-{poly(lactide)-block-poly(2-(dimethylamino) ethyl multimethacrylate)-block-poly[oligo (2-ethyl-2-oxazoline) methacrylate]} β-CD-g-(PLA-b-PDMAEMA-b-PEtOxMA) star-like block copolymers in aqueous media was investigated by dissipative particle dynamics (DPD) to explore the formation process of unimolecular micelles. The simulation results showed that using longer hydrophobic or pH-sensitive chains, shorter hydrophilic backbones, smaller hydrophilic side chain grafting density, and fewer polymer arms resulted in micellar aggregation. Furthermore, this unimolecular polymeric micelle could be used for encapsulating gold nanoparticles, whose mesoscopic structure was also explored. The gold nanoparticles tended to distribute in the middle layer formed by PDMAEMA, and the unimolecular micelles were capable of impeding gold nanoparticle aggregation. This study could help understand the formation mechanism of unimolecular micelles formed from star-like block copolymers in dilute solutions and offer a theoretical guide to the design and preparation of promising unimolecular polymeric micelles with targeting properties.

Facile In Situ Preparation and In Vitro Antibacterial Activity of PDMAEMA-Based Silver-Bearing Copolymer Micelles

“…At the same time, each water bead (W) in black color contained five water molecules. According to our previous work, Additional file 1: Table S1 showed the result of the computational interaction parameters [31, 32]. A 30 × 30 × 30 r c 3 cubic simulation box with periodic boundary conditions was utilized in all directions with 100,000 total simulation steps and 0.05 ns integration time step.…”

Co-Delivery of Imiquimod and Plasmid DNA via an Amphiphilic pH-Responsive Star Polymer that Forms Unimolecular Micelles in Water

“…The interaction parameters were calculated according to our previous method [32,36]. DPD simulations were conducted in the Mesocite module at 298.15 K in Materials Studio 5.0 (Accelrys Inc., San Diego, CA, USA).…”

Dissipative particle dynamic simulation on the assembly and release of siRNA/polymer/gold nanoparticles based polyplex

“…A cubic simulation box of 25 × 25 × 25 with periodic boundary conditions was applied in all directions, which is large enough to avoid finite size effect. With the bead density is set as 3, the cutoff radius is calculated to be 8.1 Å for a cube of for three beads . As each simulation case includes different components, their total simulation step varies to reach equilibrium.…”