Correction to Direct Investigation of Intracellular Presence of Gold Nanoparticles via Photothermal Heterodyne Imaging

Abstract

The third author's name is listed incorrectly. Instead of Randy R. Carney, it should be listed as Randy P. Carney. We apologize for any confusion this may have caused.

Electrical Method to Quantify Nanoparticle Interaction with Lipid Bilayers

“…The first were coated with alternating domains of hydrophobic (octanethiol, OT) and hydrophilic (11-mercaptoundecane sulfonate, MUS) ligands in a molar ratio of 66:34 MUS:OT (hereafter called 66-34OT). These NPs were previously found to passively penetrate cell membranes. ,− The other type of NP, hereafter referred to as 100MUS, was coated completely with the hydrophilic MUS ligand (Figure ). 100MUS NPs were previously found to penetrate cells via energy-dependent pathways and are consequently used here as a control.…”

“…Due to the potential of biomedical applications, much recent work has been directed toward the interaction between NPs and cell membranes. − Most of this research encompasses NPs in the range 10–100 nm and concludes that cells take up these NPs by one of two energy-dependent mechanisms: receptor-mediated endocytosis or transient membrane poration. − Recently however, we have discovered a type of amphiphilic gold NP coated with a mixture of ligand molecules that form stripe-like domains in their surface monolayer. These “striped” NPs spontaneously diffuse through cellular membranes into the cytosol of several types of cells through an energy-independent mechanism. ,− We believe that striped gold NPs are a subset of a large class of nanostructured materials that are capable of fusion and penetration through lipid bilayers without overt membrane disruption. Indeed recent work from other groups suggests that cellular uptake of NPs in the 2–20 nm range is not exclusively energy-dependent. ,− In addition to size, NP surface composition, ,, ligand arrangement and patterning, ,,, and charge ,, have each been shown to be critical for efficiency of passive entry pathways of cell penetration.…”

“…These “striped” NPs spontaneously diffuse through cellular membranes into the cytosol of several types of cells through an energy-independent mechanism. ,− We believe that striped gold NPs are a subset of a large class of nanostructured materials that are capable of fusion and penetration through lipid bilayers without overt membrane disruption. Indeed recent work from other groups suggests that cellular uptake of NPs in the 2–20 nm range is not exclusively energy-dependent. ,− In addition to size, NP surface composition, ,, ligand arrangement and patterning, ,,, and charge ,, have each been shown to be critical for efficiency of passive entry pathways of cell penetration. Although the mechanism(s) of passive translocation for NPs remains unidentified, several groups report that NP penetration induces critical structural changes in the lipid bilayer to allow transport to the cytosol. ,, To date there is no general understanding as to what criteria a NP should have to passively penetrate membranes.…”

High-Resolution Scanning Tunneling Microscopy Characterization of Mixed Monolayer Protected Gold Nanoparticles

“…Nanoparticles coated with striped domains have many unique structure-dependent properties that mainly derive from their interfacial interactions ,, or the presence of two polar topological defect points that can be chemically modified. , Some of these properties have led to novel applications; for example, some striped particles have been shown to spontaneously fuse with lipid bilayers and penetrate cell membranes, − leading to unconventional drug delivery approaches . Recently striped nanoparticles have been used as ultrasensitive and selective methyl mercury sensors .…”

Nanoparticles in a Capillary Trap: Dynamic Self-Assembly at Fluid Interfaces

“…Charged amphiphilic NPs represent an interesting class of nanocolloids. Amphiphilic NPs bearing a negative charge were found to exhibit an ability to penetrate and deliver a cargo into biological cells − and also to self-assemble at liquid interfaces or incorporate into the wall of surfactant vesicles . In the present study, we employed positively charged amphiphilic gold NPs recently developed in our group. , The ligand shell of the NPs was composed of a binary mixture of hydrophobic 1-undecanethiol (UDT) and hydrophilic 11-mercapto- N , N , N -tri­methyl­un­decane-1-aminium chloride/bromide (TMA) (Figure ).…”