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Enzyme-Responsive Snap-Top Covered Silica Nanocontainers

Patel, Kaushik and Angelos, Sarah and Dichtel, William R. and Coskun, Ali and Yang, Ying-Wei and Zink, Jeffrey I. and Stoddart, J. Fraser (2008) Enzyme-Responsive Snap-Top Covered Silica Nanocontainers. Journal of the American Chemical Society, 130 (8). pp. 2382-2383. ISSN 0002-7863. doi:10.1021/ja0772086.

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Mesoporous silica nanoparticles, capable of storing a payload of small molecules and releasing it following specific catalytic activation by an esterase, have been designed and fabricated. The storage and release of the payload is controlled by the presence of [2]rotaxanes, which consist of tri(ethylene glycol) chains threaded by α-cyclodextrin tori, located on the surfaces of the nanoparticles and terminated by a large stoppering group. These modified silica nanoparticles are capable of encapsulating guest molecules when the [2]rotaxanes are present. The bulky stoppers, which serve to hold the tori in place, are stable under physiological conditions but are cleaved by the catalytic action of an enzyme, causing dethreading of the tori and release of the guest molecules from the pores of the nanoparticles. These snap-top covered silica nanocontainers (SCSNs) are prepared by a modular synthetic method, in which the stoppering unit, incorporated in the final step of the synthesis, may be changed at will to target the response of the system to any of a number of hydrolytic enzymes. Here, the design, synthesis, and operation of model SCSNs that open in the presence of porcine liver esterase (PLE) are reported. The empty pores of the silica nanoparticles were loaded with luminescent dye molecules (rhodamine B), and stoppering units that incorporate adamantyl ester moieties were then attached in the presence of α-cyclodextrin using the copper-catalyzed azide−alkyne cycloaddition (CuAAC), closing the SCSNs. The release of rhodamine-B from the pores of the SCSN, following PLE-mediated hydrolysis of the stoppers, was monitored using fluorescence spectroscopy.

Item Type:Article
Related URLs:
URLURL TypeDescription Information
Dichtel, William R.0000-0002-3635-6119
Coskun, Ali0000-0002-4760-1546
Stoddart, J. Fraser0000-0003-3161-3697
Additional Information:© 2008 American Chemical Society. Received September 17, 2007. Publication Date (Web): January 31, 2008. The collaboration was supported by the NSF (Grants CHE 0507929 and DMR 0346601) and the University of California Toxic Substances Research and Teaching Program.
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University of CaliforniaUNSPECIFIED
Issue or Number:8
Record Number:CaltechAUTHORS:20170425-091134802
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Official Citation:Enzyme-Responsive Snap-Top Covered Silica Nanocontainers Kaushik Patel, Sarah Angelos, William R. Dichtel, Ali Coskun, Ying-Wei Yang, Jeffrey I. Zink, and J. Fraser Stoddart Journal of the American Chemical Society 2008 130 (8), 2382-2383 DOI: 10.1021/ja0772086
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:76903
Deposited By: Tony Diaz
Deposited On:25 Apr 2017 16:32
Last Modified:15 Nov 2021 17:03

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