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Catalytic mesoporous Janus nanomotors for active cargo delivery.

Ma X, Hahn K, Sanchez S - J. Am. Chem. Soc. (2015)

Bottom Line: The chemically powered Janus nanomotors present active diffusion at low H2O2 fuel concentration (i.e., <3 wt %).Their apparent diffusion coefficient is enhanced up to 100% compared to their Brownian motion.Due to their mesoporous architecture and small dimensions, they can load cargo molecules in large quantity and serve as active nanocarriers for directed cargo delivery on a chip.

View Article: PubMed Central - PubMed

Affiliation: †Max Planck Institute for Intelligent Systems Institution, Heisenbergstraße 3, 70569 Stuttgart, Germany.

ABSTRACT
We report on the synergy between catalytic propulsion and mesoporous silica nanoparticles (MSNPs) for the design of Janus nanomotors as active cargo delivery systems with sizes <100 nm (40, 65, and 90 nm). The Janus asymmetry of the nanomotors is given by electron beam (e-beam) deposition of a very thin platinum (2 nm) layer on MSNPs. The chemically powered Janus nanomotors present active diffusion at low H2O2 fuel concentration (i.e., <3 wt %). Their apparent diffusion coefficient is enhanced up to 100% compared to their Brownian motion. Due to their mesoporous architecture and small dimensions, they can load cargo molecules in large quantity and serve as active nanocarriers for directed cargo delivery on a chip.

No MeSH data available.


Related in: MedlinePlus

Characterization of Janus mesoporous nanomotors. (a) TEM-BFimagesof JMSNM(40 nm)-Pt(2 nm), JMSNM(65 nm)-Pt(2 nm), and JMSNM(90 nm)-Pt(2nm), from left to right, respectively. (b) STEM-HAADF image and elementmapping of JMSNM(65 nm)-Pt(2 nm) by EDX.
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fig1: Characterization of Janus mesoporous nanomotors. (a) TEM-BFimagesof JMSNM(40 nm)-Pt(2 nm), JMSNM(65 nm)-Pt(2 nm), and JMSNM(90 nm)-Pt(2nm), from left to right, respectively. (b) STEM-HAADF image and elementmapping of JMSNM(65 nm)-Pt(2 nm) by EDX.

Mentions: Janus mesoporous silica nanomotors (JMSNMs)were fabricated bydepositing a thin layer (2 nm) of Pt onto the MSNPs monolayers byelectron-beam (e-beam) evaporation at zero degree, leading to twodifferent faces of each side of the nanoparticles. Hence, the mesoporesat the noncoated side of the JMSNM are still accessible to small molecules,for cargo loading. Transmission electron microscopy (TEM) bright-field(BF) images in Figure 1a show JMSNM of differentsizes with Pt coating layers as a dark color. Due to the ultrathinlayer deposition, instead of forming a uniform and continuous smoothcoating layer, the catalytic layers form Pt islands which were reportedto exhibit better catalytic performance than smooth ones.49,50 JMSNM(65 nm)-Pt(2 nm) was chosen for element mapping by scanningtransmission electron microscopy (STEM) high-angle annular dark field(HAADF) and energy-dispersive X-ray spectroscopy (EDX) (Figure 1b). Corresponding EDX spectra of the Pt coated andnoncoated sides were both acquired (Figure S3 in the SI). The Janus structure was clearly outlined by the elementmapping, as both oxygen (O: red) and silicon (Si: green) elementsshow a spherical shape while the Pt (blue) element covers one-halfof a sphere.


Catalytic mesoporous Janus nanomotors for active cargo delivery.

Ma X, Hahn K, Sanchez S - J. Am. Chem. Soc. (2015)

Characterization of Janus mesoporous nanomotors. (a) TEM-BFimagesof JMSNM(40 nm)-Pt(2 nm), JMSNM(65 nm)-Pt(2 nm), and JMSNM(90 nm)-Pt(2nm), from left to right, respectively. (b) STEM-HAADF image and elementmapping of JMSNM(65 nm)-Pt(2 nm) by EDX.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4440854&req=5

fig1: Characterization of Janus mesoporous nanomotors. (a) TEM-BFimagesof JMSNM(40 nm)-Pt(2 nm), JMSNM(65 nm)-Pt(2 nm), and JMSNM(90 nm)-Pt(2nm), from left to right, respectively. (b) STEM-HAADF image and elementmapping of JMSNM(65 nm)-Pt(2 nm) by EDX.
Mentions: Janus mesoporous silica nanomotors (JMSNMs)were fabricated bydepositing a thin layer (2 nm) of Pt onto the MSNPs monolayers byelectron-beam (e-beam) evaporation at zero degree, leading to twodifferent faces of each side of the nanoparticles. Hence, the mesoporesat the noncoated side of the JMSNM are still accessible to small molecules,for cargo loading. Transmission electron microscopy (TEM) bright-field(BF) images in Figure 1a show JMSNM of differentsizes with Pt coating layers as a dark color. Due to the ultrathinlayer deposition, instead of forming a uniform and continuous smoothcoating layer, the catalytic layers form Pt islands which were reportedto exhibit better catalytic performance than smooth ones.49,50 JMSNM(65 nm)-Pt(2 nm) was chosen for element mapping by scanningtransmission electron microscopy (STEM) high-angle annular dark field(HAADF) and energy-dispersive X-ray spectroscopy (EDX) (Figure 1b). Corresponding EDX spectra of the Pt coated andnoncoated sides were both acquired (Figure S3 in the SI). The Janus structure was clearly outlined by the elementmapping, as both oxygen (O: red) and silicon (Si: green) elementsshow a spherical shape while the Pt (blue) element covers one-halfof a sphere.

Bottom Line: The chemically powered Janus nanomotors present active diffusion at low H2O2 fuel concentration (i.e., <3 wt %).Their apparent diffusion coefficient is enhanced up to 100% compared to their Brownian motion.Due to their mesoporous architecture and small dimensions, they can load cargo molecules in large quantity and serve as active nanocarriers for directed cargo delivery on a chip.

View Article: PubMed Central - PubMed

Affiliation: †Max Planck Institute for Intelligent Systems Institution, Heisenbergstraße 3, 70569 Stuttgart, Germany.

ABSTRACT
We report on the synergy between catalytic propulsion and mesoporous silica nanoparticles (MSNPs) for the design of Janus nanomotors as active cargo delivery systems with sizes <100 nm (40, 65, and 90 nm). The Janus asymmetry of the nanomotors is given by electron beam (e-beam) deposition of a very thin platinum (2 nm) layer on MSNPs. The chemically powered Janus nanomotors present active diffusion at low H2O2 fuel concentration (i.e., <3 wt %). Their apparent diffusion coefficient is enhanced up to 100% compared to their Brownian motion. Due to their mesoporous architecture and small dimensions, they can load cargo molecules in large quantity and serve as active nanocarriers for directed cargo delivery on a chip.

No MeSH data available.


Related in: MedlinePlus