Monte Carlo Simulations of Metallo‐Supramolecular Micelles

Abstract

Using Monte Carlo simulations we show that the equilibrium properties of metallo-supramolecular micelles are determined by the competition of 2:1 and 1:1 metal-ligand complexation in the bulk and on the surface as well as steric interactions between the neighboring corona blocks attached to the surface. We predict that by increasing the association energy for the second metal-ligand bond, or decreasing the corona block length one can achieve a larger core surface coverage for metallo-supramolecular micelles. Compared to covalently bonded block copolymer micelles, we show that metallo-supramolecular micelles have smaller monomer and end group density, especially in the vicinity of the core, which may lead to experimentally observed aggregation.

Optimization of a Nanomedicine-Based Silicon Phthalocyanine 4 Photodynamic Therapy (Pc 4-PDT) Strategy for Targeted Treatment of EGFR-Overexpressing Cancers

“…In fact, this resulted in an apparent decrease in targeting and internalization in our in vitro experimental conditions. This is in accordance with the theoretical findings of nanomedicine design optimization reported by Wang et al, which reports that increasing the number of ligand decorations on a nanoparticle surface does not necessarily guarantee a corresponding increase in receptor targeting (and internalization in the case of receptors which undergo endocytosis), due to possible entropic barriers associated with the conformational changes that a ligand-tethered random coil polymer (e.g., PEG in our case) and heterogeneously distributed receptors (e.g., EGFRs on a nonplanar cell surface) may possess . It is also to be noted that, for the cell-targeted assays with the GE11-modified micelles, the intracellular fluorescence at short time periods (up to 6 h) appears punctate while after longer time periods (e.g., 24 h) the fluorescence seems to be distributed more homogenously throughout the cytoplasm.…”

“…This is in accordance with the theoretical findings of nanomedicine design optimization reported by Wang et al, which reports that increasing the number of ligand decorations on a nanoparticle surface does not necessarily guarantee a corresponding increase in receptor targeting (and internalization in the case of receptors which undergo endocytosis), due to possible entropic barriers associated with the conformational changes that a ligand-tethered random coil polymer (e.g., PEG in our case) and heterogeneously distributed receptors (e.g., EGFRs on a nonplanar cell surface) may possess. 38 It is also to be noted that, for the cell-targeted assays with the GE11modified micelles, the intracellular fluorescence at short time periods (up to 6 h) appears punctate while after longer time periods (e.g., 24 h) the fluorescence seems to be distributed more homogenously throughout the cytoplasm. This may be indicative of the fact that at the shorter incubation periods the internalized micelles (hence Pc 4 fluorescence) are within the endosomal spaces in the cells, while over time the endosomal/lysosomal acidic environment may degrade and disassemble the micelles, resulting in release and distribution/partitioning of the hydrophobic Pc 4 into intracellular organelle membranes (e.g., mitochondria, Golgi, ER, etc.…”

Metallo‐Supramolecular Nanogels for Intracellular pH‐Responsive Drug Release

“…Since the Nobel Prize in Chemistry has been awarded to Pedersen, Lehn, and Cram in 1987, [ 1 ] supramolecular chemistry based on non-covalent interactions such as multiple hydrogen bonding, [ 2 ] host-guest recognition, [3][4][5][6] hydrophobic interaction, [ 7 ] π-π stacking, [ 8 ] and metal-ligand coordination [9][10][11] has garnered tremendous attentions. Over the past years, extensive efforts have been devoted to the construction of functional supramolecular nanosystems for applications in catalysis, energy conversion, sensing, and biomedicine, especially in the biomedical and benzene-guest, which could present a pH-responsive nanoreservoir for effi cient targeted drug delivery to cancer cells.…”