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Liangwei Qu

Publications and source records attributed to Liangwei Qu.

6 recordsLinked to original sources
PubMed2005

NMR detection of single-walled carbon nanotubes in solution.

The detection of nanotube carbons in solution by (13)C NMR is reported. The highly soluble sample was from the functionalization of (13)C-enriched single-walled carbon nanotubes (SWNTs) with diamine-terminated oligomeric poly(ethylene glycol) (PEG(1500N)). The ferromagnetic impurities due to the residual metal catalysts were removed from the sample via repeated magnetic separation. The nanotube carbon signals are broad but partially resolved into two overlapping peaks, which are tentatively assigned to nanotube carbons on semiconducting (upfield) and metallic (downfield) SWNTs. The solid-state NMR signals of the same sample are similarly resolved. Mechanistic and practical implications of the results are discussed.

Journal Article↗
PubMed2005

Polymeric nanoparticles from rapid expansion of supercritical fluid solution.

In this concept paper we highlight applications of supercritical fluid technology in particle formation and production, especially some recent advances in the rapid expansion of supercritical solutions (RESS) processing technique. We also highlight the simple but significant modification to the traditional RESS by using a liquid solvent or solution at the receiving end of the supercritical solution expansion, or the rapid expansion of a supercritical solution into a liquid solvent (RESOLV), and applications of the technique to the preparation of nanoparticles. In particular, successes and challenges in the use of RESOLV for nanoscale (<100 nm) polymeric particles and the subsequent protection of the suspended nanoparticles from agglomeration are discussed.

Journal Article↗
PubMed2005

Visualizing adhesion-induced agglutination of Escherichia coli with mannosylated nanoparticles.

Polymeric nanoparticles covalently functionalized with derivatized D-mannose molecules were synthesized and characterized. These nanoparticles have an average size of approximately 160 nm in diameter, thus bearing a large number of surface-tethered mannose moieties for multivalent interactions with adhesins on bacterial cells. Specifically, the mannosylated nanoparticles bind strongly with Escherichia coli, allowing the convenient visualization of adhesion interactions under a conventional electron microscope. Since a single nanoparticle is capable of binding more than one cell, the adhesion interactions result in significant nanoparticle-mediated cell agglutination according to electron microscopy imaging. Potential applications of the mannosylated nanoparticles in the inhibition of enteropathogenic infections are discussed.

Adhesins, Escherichia coli↗