ANYL 340 |
| Luminescent nanocrystals show great promise in molecular detection. Their distinct optical properties, such as compositionally tunable emissions and low susceptibility to photobleaching, give them advantages over organic dyes. Among all the II-VI nanocrystals, ZnO is particularly intriguing due to its low intrinsic toxicity and long history for industrial applications. Recently, development on photoluminescent ZnO-based nanocrystals demonstrated improved quantum yield and intrigued us to apply them as molecular sensors for biological and chemical detection. In this report, we describe the preparation of highly soluble and stable ZnO colloidal solution via surface modification with a silane shell. We have successfully increased its long-term stability and cast it as stable films. In the past, II-VI nanocrystals have been applied as emitters of fluorescence resonance energy transfer assays and fluorescence-quenching assays. They are also used to recognize inorganic ions based on the different quantum yields resulting from changes in surface charge. Even though the photostability of luminescent nanocrystals are very sensitive to the surface structure, to our knowledge, control of photostability has never been strategically applied for detection. In this report, we will also demonstrate selective detection of functional molecules by controlling the photostability of the nanocrystals' protection layer. |
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Analytical Approaches: Novel Materials
1:30 PM-4:40 PM, Thursday, 14 September 2006 Moscone Center -- Room 130, Oral
Division of Analytical Chemistry |