Home
This Title All WIREs
WIREs RSS Feed
How to cite this WIREs title:
WIREs Nanomed Nanobiotechnol
Impact Factor: 6.14

What is the role of curvature on the properties of nanomaterials for biomedical applications?

Full article on Wiley Online Library:   HTML PDF

Can't access this content? Tell your librarian.

The use of nanomaterials for drug delivery and theranostics applications is a promising paradigm in nanomedicine, as it brings together the best features of nanotechnolgy, molecular biology, and medicine. To fully exploit the synergistic potential of such interdisciplinary strategy, a comprehensive description of the interactions at the interface between nanomaterials and biological systems is not only crucial, but also mandatory. Routine strategies to engineer nanomaterial‐based drugs comprise modifying their surface with biocompatible and targeting ligands, in many cases resorting to modular approaches that assume additive behavior. However, emergent behavior can be observed when combining confinement and curvature. The final properties of functionalized nanomaterials become dependent not only on the properties of their constituents but also on the geometry of the nano‐bio interface, and on the local molecular environment. Modularity no longer holds, and the coupling between interactions, chemical equilibrium, and molecular organization has to be directly addressed in order to design smart nanomaterials with controlled spatial functionalization envisioning optimized biomedical applications. Nanoparticle's curvature becomes an integral part of the design strategy, enabling to control and engineer the chemical and surface properties with molecular precision. Understanding how nanoparticle size, morphology, and surface chemistry are interrelated will put us one step closer to engineering nanobiomaterials capable of mimicking biological structures and their behaviors, paving the way into applications and the possibility to elucidate the use of curvature by biological systems. WIREs Nanomed Nanobiotechnol 2016, 8:334–354. doi: 10.1002/wnan.1365 This article is categorized under: Diagnostic Tools > Biosensing Diagnostic Tools > Diagnostic Nanodevices Therapeutic Approaches and Drug Discovery > Emerging Technologies
Design parameters for optimized smart nanomaterials for biomedical applications. (Reprinted with permission from Ref . Copyright 2012 The Royal Society of Chemistry; Ref . Copyright 2010 The Royal Society of Chemistry)
[ Normal View | Magnified View ]
(a) Scheme of a polymer‐coated NP interacting with a planer surface. (b) Contour maps of the polymer volume fractions for the NP functionalized with short (left panel) and long (right panel) neutral polymers at a position close to the surface. Top panels (A–B) correspond to chains with no lateral mobility, while the figures in the bottom (C–D) correspond the mobile tethered chains. R = 5 nm, σ = 0.25 long chains/nm2, σ = 0.5 short chains/nm2, Nshort = 20 segments, Nlong = 20 segments. (c) Free energy as a function of the distance between the NP and the surface. (Reprinted with permission from Ref . Copyright 2012 The Royal Society of Chemistry)
[ Normal View | Magnified View ]
(a and b) Adsorption isotherms for lysozyme (Lyz) and α‐chymotrypsin (ChT) onto gold nanospheres (AuNS 10.6 nm diameter) and nanorods (AuNR 10.3 nm diameter, 36.4 nm length). Solid lines correspond to the fit according to the Langmuir equation. Dotted lines indicate estimated surface coverage at the given loading. (c) Adsorption isotherm for the ChT onto AuNRs, evidencing the multilayer nature of the process. (d) Schematic representation of protein adsorption to AuNP. In Region I, both proteins adsorb onto the nanoparticle with almost none structural modification. In Region II, protein‐surface interactions induce conformational changes. In Region III, protein–protein interactions give rise to multilayer adsorption. (Reprinted with permission from Ref . Copyright 2011 Elsevier)
[ Normal View | Magnified View ]
(a) Schematic representation of the collapse of the end‐grafted polymer layer on a Au‐NP due to a change in the solvent quality, and the shift in the position of the LSPR peak, Δλcollapse, this collapse induces. (b) Effect of the Au‐NP core size (R) and the chain length (N) in the change in the position of the LSPR band (Δλcollapse, panel b) and in the average polymer volume fraction of the film upon collapse (Δϕcollapse, panel c). Surface density is σ = 0.5 nm−2. (Reprinted with permission from Ref . Copyright 2012 American Chemical Society)
[ Normal View | Magnified View ]
(a) Scheme of the simulation model based on explicit calculation of solvent‐accessible surface area (blue surface). (b) Representation of the three surface morphologies simulated. (c) Simulation results for the change in free energy for embedding into the membrane as a function of AuNP core diameter. A strong dependence is observed with respect to the NP diameter and monolayer composition, but hardly non with respect to the arrangement of surface ligands. The dashed line indicates the critical size below which embedding would be favorable. (d) Comparison of simulation results from (c) to lipid membrane experiments. (Reprinted with permission from Ref . Copyright 2013 American Chemical Society)
[ Normal View | Magnified View ]
Variation of pH as a function of the distance from the surface for (a) planar, (b) cylindrical (1 nm diameter), and (c) spherical (1 nm diameter) NP grafted with weak polyelectrolytes (surface coverage = 0.25 nm−2, polymer chain length = 50, and pKa = 7). The colors correspond to different salt concentrations: 1 (black), 0.1 (red), 0.01 (green), and 0.001 M (blue). A concentration of 0.1 M is the closest to physiological conditions. The insets show the fraction of charged groups as a function of the distance from the surface. The solution's bulk pH is 7. (Reprinted with permission from Ref . Copyright 2006 John Wiley & Sons, Inc.)
[ Normal View | Magnified View ]
(a) Scheme of a polymer‐coated NP interacting with a lipid membrane. Neutral polymer chains are in red, while the polybases (pKa = 7.5) with their ligand‐end group are in black. Uncharged lipids are in purple, overexpressed receptors in red, and negatively charged lipids in green. (b) Contour maps of the polymer volume fractions for both neutral polymers (left panel) and polybase (right panel) for a NP close to the lipid layer for a pH = 7.5 and a salt concentration of 0.10 M. R = 2.5 nm, σ = 0.20 molecules/nm2, N = 20 segments. (c) Coated NP interacting with a lipid membrane with both overexpressed receptors and charged lipids. Left panel: Contour map of the fraction of charged groups of the polybases on a NP close to the lipid membrane. The conditions are the same as in (b). Right panel: Contour map of the fraction of charged lipids in the membrane. The center of the NP is at (x; y) = (0; 0) and 2.0 nm above the membrane surface. The conditions are the same as in (b). (d) Free energy as a function of the distance between the NP surface and the lipid layer. The conditions are the same as in (b). The colors correspond to the three membranes modeled: no overexpressed receptors and negatively charged lipids (red), neutral lipid membrane with overexpressed receptors (magenta), and membranes with both overexpressed receptors and charged lipids (blue). (Reprinted with permission from Ref . Copyright 2013 The Royal Society of Chemistry)
[ Normal View | Magnified View ]
(a) Scheme of a PEGylated Au‐NP. (b) PEG volume as a function of the grafting density for NP of different sizes. (c) Adsorbed serum protein density as a function of PEG grafting density. (d–g) Molecular composition of the adsorbed protein layer for the 15, 30, 60, and 90 nm Au‐NPs respectively. (Reprinted with permission from Ref . Copyright 2012 American Chemical Society)
[ Normal View | Magnified View ]
(a) Scheme of the combinatorial design of the Au‐NP library. 105 surface‐modified NP were prepared by grafting Au‐NPs of 15, 30, and 60 nm diameter with 67 surface ligands of different nature: neutral (green), cationic (blue), or anionic (red). (b) Total adsorbed serum protein density, and (c) net cell association (log2‐transformed) for each formulation in the library. (Reprinted with permission from Ref . Copyright 2014 American Chemical Society)
[ Normal View | Magnified View ]
(a) Fractions of dissociated MUA ligands as a function of pH. The theoretical charge fraction (black curve), f, was calculated with the molecular theory (MT). The red curve is calculated for free MUA in solution using the Henderson–Hasselbalch equation. The inset shows the experimental pKa of NP's ligands. Diameter of the NP's metal core = 4.1 nm, salt concentration (tetramethylammonium chloride, TMACl) = 0.08 M. (b) The apparent pKa’s of Au‐MUA NPs of different sizes plotted as a function of TMACl concentration. Open markers correspond to experimental data; lines were calculated with MT. pKa for free MUA is ~4.8. (Reprinted with permission from Ref . Copyright 2011 American Chemical Society)
[ Normal View | Magnified View ]

Browse by Topic

Diagnostic Tools > Diagnostic Nanodevices
Therapeutic Approaches and Drug Discovery > Emerging Technologies
Diagnostic Tools > Biosensing

Access to this WIREs title is by subscription only.

Recommend to Your
Librarian Now!

The latest WIREs articles in your inbox

Sign Up for Article Alerts