Surface Presentation of Functional Peptides in Solution Determines Cell Internalization Efficiency of TAT Conjugated Nanoparticles

Functionalizing nanoparticles with cell-penetrating peptides is a popular choice for cellular delivery. We investigated the effects of TAT peptide concentration and arrangement in solution on functionalized nanoparticles’ efficacy for membrane permeation. We found that cell internalization correlates with the positive charge distribution achieved <i>prior</i> to nanoparticle encountering interactions with membrane. We identified a combination of solution based properties required to maximize the internalization efficacy of TAT-functionalized nanoparticles

Comparison of embedded atom method potentials for small aluminium cluster simulations

In this paper, we present a comparison of the performance of a series of embedded atom method potentials for the evaluation of bulk and small aluminium cluster geometries and relative energies, against benchmark density functional theory calculations. In general, the non-pairwise potential-B (NP-B), which was parametrized against Al cluster data, performs the best

Surface Dynamics and Ligand−Core Interactions of Quantum Sized Photoluminescent Gold Nanoclusters

Quantum-sized metallic clusters protected by biological ligands represent a new class of luminescent materials; yet the understanding of structural information and photoluminescence origin of these ultrasmall clusters remains a challenge. Herein we systematically study the surface ligand dynamics and ligand−metal core interactions of peptide-protected gold nanoclusters (AuNCs) with combined experimental characterizations and theoretical molecular simulations. We show that the peptide sequence plays an important role in determining the surface peptide structuring, interfacial water dynamics and ligand−Au core interaction, which can be tailored by controlling peptide acetylation, constituent amino acid electron donating/withdrawing capacity, aromaticity/hydrophobicity and by adjusting environmental pH. Specifically, emission enhancement is achieved through increasing the electron density of surface ligands in proximity to the Au core, discouraging photoinduced quenching, and by reducing the amount of surfacebound water molecules. These findings provide key design principles for understanding the surface dynamics of peptideprotected nanoparticles and maximizing the photoluminescence of metallic clusters through the exploitation of biologically relevant ligand properties