Bioinspired Polyethylene Glycol Coatings for Reduced Nanoparticle–Protein Interactions

Abstract

Nanoparticles (NPs) and other engineered nanomaterials have great potential as nanodrugs or nanomedical devices for biomedical applications. However, the adsorption of proteins in blood circulation or similar physiological fluids can significantly alter the surface properties and therapeutic response induced by most nanomaterials. For example, interaction with proteins can change the bloodstream circulation time and availability of therapeutic NPs or hinder the accumulation in their desired target organs. Proteins can also trigger or prevent agglomeration. By combining experimental and computational approaches, we have developed NPs carrying polyethylene glycol (PEG) polymeric coatings that mimic the surface charge distribution of proteins typically found in blood, which are known to show low aggregation under normal blood conditions. Here, we show that NPs with coatings based on apoferritin or human serum albumin display better antifouling properties and weaker protein interaction compared to similar NPs carrying conventional PEG polymeric coatings.

Unraveling the Nano–Bio Interface Interactions of a Lipase Adsorbed on Gold Nanoparticles under Laser Excitation

“…To gain further insight into the effect of the temperature increase driven by the LSPR stimulus, we conducted molecular dynamics (MD) simulations to determine the unfolding of free CALB and CALB@AuNPs via CD and Raman analyses. Free CALB (PDB: 1TCA) in solution at different arbitrary temperatures ( T *, in LJ units) was analyzed through coarse-grained molecular dynamics simulations using a large-scale atomic/molecular massively parallel simulator (LAMMPS) following a previously developed procedure to account for the electric and H-bond interactions between the NPs and the adsorbing protein. , To evaluate the enzymatic conformational changes in both the free and AuNP-adsorbed conditions at different temperatures, we followed the evolution of the root-mean-square displacement (RMSD) and the radial distribution function of the overall structure of the enzyme. Additionally, during the time course, the catalytic triad of CALB, which is composed of the residues Ser105-Asp187-His224, was monitored to determine the conformation at which the activity decreases as a function of the enzyme denaturation.…”

“…Additionally, in a previous report, a numerical protocol was developed in which the interactions between the different residues and the surface charges of the NPs were included . Hence, we developed a coarse-grained representation of the protein-NP system based on the one used in our previous study . The acceptor and donor states are determined from the ζ-potential using the expression from Ohshima et al σ ζ = 2 ε r ε 0 κ k T e sin 0em0.25em⁡ h sin 0em0.25em⁡ h ( e ζ 2 k T ) true[ 1 + 1 κ a true( 2 cos 0em0.25em⁡ h 2 ( e ζ 4 k T ) true) + 1 ( κ a false) 2 true( 8 0em0.25em⁡ ln [ cos 0em0.25em⁡ h cos 0em0.25em⁡ h ( e ζ 4 k T ) ] sin 0em0.25em⁡ h 2 ( e ζ 2 k T ) true) true] 1 / 2 where ε r = 80.2 is the relative permittivity of water at room temperature, 8.85 × 10ε 0 –12 C/Nm 2 is the permittivity of vacuum, κ –1 is the Debye length estimated at 0.7 nm under physiological conditions, e = 1.6 × 10 –19 C is the elementary electric charge, kT = 4.11 × 10 –19 J is the thermal energy, and the ζ potential is estimated in the experiments.…”

Targeting the Spike: Repurposing Mithramycin and Dihydroergotamine to Block SARS-CoV-2 Infection

“…45 All attractive interactions between the spike protein and the drugs were represented using a sigmoidal-type potential called U ATT , which we extensively used in coarse-grained protein models to represent residue−residue interactions. 34,46,47 r ( ) 1…”

“…All attractive interactions between the spike protein and the drugs were represented using a sigmoidal-type potential called U A T T , which we extensively used in coarse-grained protein models to represent residue–residue interactions. ,, italicU normalATT ( r ) = normal1 normal1.0 + normale − normal2.5 ( r c − r ) where r c = 4.0 Å is the hard-core radius of each residue; the solvent is implicit. While all excluded volume interactions are represented with a Weeks–Chandler–Andersen potential, a Lennard-Jones potential shifted to zero from the distance corresponding to the minimum to infinite …”

Efficient One‐Step Passivation of Polyurethane Using Transurethanization

“…For example, loading antibiotics into the material can limit bacterial development for a restricted period of time. [4] The formation of a hydrophilic polymer brush such as PEG, [5,6] polysaccharides, [7] polyzwitterions [8] at the surface of materials constitutes a strategy to afford antifouling properties. [9][10][11] PEG polymers are known to provide antiadhesive properties to the surfaces toward bacteria [12] and proteins, [13,14] and to improve the blood compatibility of polyurethane (PU) materials.…”