Navigation Links
Photoluminescence Spectroscopy of Quantum Dots, monitored by the Spex FluoroMax


The optical properties of quantum dots (QDs) have potential applications in optoelectronics, biosensing and biolabeling, memory devices, and sources of laser light. For example, alloyed CdSeTe QDs are shown herein to possess a nonlinear change in their photoluminescence spectra, correlated to size and composition, as monitored by the versatile Spex FluoroMax spectrofluorometer. The QDs' emission wavelength can be as high as 850 nm, which may be useful for imaging deeper into living tissue than visible light can penetrate.


Experiment
The procedure for synthesizing alloyed CdSeTe QDs (2.7-8.6 nm diameter) from pure CdO, Se shot, and Te powder in tri-n-octylphosphine oxide and hexadecylamine is given elsewhere (1). The nanoparticles were purified by precipitation and centrifugation, then stored at room temperature. Absorption spectra were monitored on a Shimadzu spectrophotometer (slit = 1.0 nm). Fendler, et al's method (2) for finding the absorption onset and band-gap energies was used with the absorption data. Photoluminescence spectra were recorded using a Spex FluoroMax spectrofluorometer. The emission spectra were performed with an excitation wavelength of 475 nm and slit-widths of 2.0 nm. All spectra were corrected for the detector's wavelength-dependent response.


Results
QDs in layered solutions (CCL4 below; water, above) under ambient and UV light are shown in Figure 1. QDs coated with tri-n-octyl phosphine oxide remain in the organic layer, while those coated with m
'"/>

Source:


Page: All 1 2 3 4

Related biology technology :

1. Improved Quantitative Selectivity of Clenbuterol in Human Urine using High Resolution on the TSQ Quantum Mass Spectrometer
2. Bioanalytical Method Intraday Validation for the Quantitation of Paroxetine in Bovine Plasma using the TSQ Quantum Mass Spectrometer
3. Quantitation of Acrylamide in Food Samples on the Finnigan TSQ Quantum Discovery by LC/APCI-MS/MS
4. Increased Analyte Sensitivity through the Utility of Enhanced Mass-Resolution on the FinniganTSQ Quantum Discovery
5. FluoroMax multiwavelength capability
Post Your Comments:
(Date:5/4/2015)... Genedata, a leading provider of ... science research, today announced the release of ... its enterprise solution for biologics R&D. This first-in-class ... discovery and development of novel biotherapeutics. Version 5.0 ... protein optimization and developability requirements. Genedata will present ...
(Date:5/4/2015)... 2015 China Cord Blood Corporation (NYSE: ... leading provider of cord blood collection, laboratory ... services, today announced that the Company has been informed ... Hong Kong listed company and a ... agreement (the "Agreement") to purchase the Company,s outstanding 7% ...
(Date:5/4/2015)... 2015   Intrexon Corporation (NYSE: XON ... financial results after the market closes on May 11, ... day at 5:30 PM ET to discuss the results ... conference call may be accessed by dialing 1-888-346-3959 (Domestic ... "Intrexon Conference Call."  Participants may also access the live ...
(Date:5/1/2015)...  Northwest Biotherapeutics (NASDAQ: NWBO ) ("NW Bio"), ... for solid tumor cancers, announced today that the Company ... a $40 million investment from Woodford investment funds in ... million in NW Bio on November 19, 2014.  On ... the Company for a further $40 million investment in ...
Breaking Biology Technology:Genedata Biologics 5.0 – Antibody Engineering and Developability Assessment Advances 2Genedata Biologics 5.0 – Antibody Engineering and Developability Assessment Advances 3Genedata Biologics 5.0 – Antibody Engineering and Developability Assessment Advances 4China Cord Blood Corporation Receives Notice of a Transaction Regarding its 7% Senior Convertible Notes Due 2017 Held by KKR 2China Cord Blood Corporation Receives Notice of a Transaction Regarding its 7% Senior Convertible Notes Due 2017 Held by KKR 3Intrexon to Announce First Quarter 2015 Financial Results on Monday, May 11, 2015 2NW Bio Closes On $28.5 Million Second Tranche Of Woodford $40 Million Financing 2NW Bio Closes On $28.5 Million Second Tranche Of Woodford $40 Million Financing 3
... CytoDyn , a New Mexico-based biotechnology company, has ... manufacture its DNA-based, pre-flu vaccine. , ,Located ... the biomanufacturing facility is designed to manufacture clinical-grade biological ... trials. CytoDyn hopes to have clinical trials underway before ...
... David M. Kettner, who has served as in-house counsel for ... post after March 30 to become chief intellectual property counsel ... emphasized biotech patent prosecution and intellectual property licensing, will continue ... for a period of time after March 30. At WARF, ...
... Corp . and Imaxio S.A. (Saint-Beauzire, France) ... to manufacture and sell OverExpress bacterial cells ... will retain the right to license the use of ... the cells to commercial licensees. No license will be ...
Cached Biology Technology:Lucigen Corp. enters global licensing agreement 2
(Date:4/8/2015)... , April 8, 2015  Infinisource, a leading ... services, and Morpho, a leading supplier of biometric ... produce the market,s most advanced biometrically-enabled time clock, ... NXG time clock is setting a bold, new ... data for the small and mid-size employer. When ...
(Date:4/2/2015)... In the current eight ... the strongest competitors, showing outstanding performance in recognition ... is capable of a throughput of 5.000.000 fingerprints ... be ten times faster than most competitors and ...      (Photo: http://photos.prnewswire.com/prnh/20150402/738673-a ) , ...
(Date:4/2/2015)... -- According to preliminary estimates Fingerprint Cards, ... than 125 MSEK. This exceeds the guidance provided by ... for Q1 2015 would be in line with the ... The operating result for the first quarter is estimated ... will as previously communicated be published on May 21. ...
Breaking Biology News(10 mins):iSolved Time Clock Offers Unmatched Accuracy due to Morpho Biometrics 2iSolved Time Clock Offers Unmatched Accuracy due to Morpho Biometrics 3DERMALOG AFIS Emerges as Performance Winner in NIST Benchmark Test 2DERMALOG AFIS Emerges as Performance Winner in NIST Benchmark Test 3Fingerprint Cards Revises Revenues for Q1 2015 2
... A team of scientists from the University of Maryland ... the Gulf of Mexico later this summer to study the ... and fish communities in the northern Gulf. The National Science ... for the expedition, which will be led by Laboratory Director ...
... held June 21-22, 2010, in Baltimore, Md., at ... business, science, education and government leaders to discuss ... glass materials used in advanced armor, semiconductors, turbines, ... filters, nuclear reactors and high-strength "smart" construction materials. ...
... that the Earth has been gradually warming as the result ... to stop it, according to a new survey by researchers ... The survey was conducted by Woods Institute Senior Fellow ... at Stanford, with funding from the National Science Foundation. The ...
Cached Biology News:Large majority of Americans still believe in global warming, Stanford poll finds 2Large majority of Americans still believe in global warming, Stanford poll finds 3
Collected from sexually mature, mixed sex, mixed breed guinea pigs. Pricing: $120/unit for 1 - 10 units...
... PlusOne Silver Staining Kit, Protein, ... Heukeshoven and Dernick (1), the kit ... gel electrophoresis systems.Silver Staining Kit, Protein ... of proteins in polyacrylamide gels in ...
Cyno macaque plasma and serum - various quantities available...
3'-O-Methylguanosine 5'-Triphosphate, Sodium, 1 umol. Category: Nucleotides & Enzymes & Biochemicals, Nucleotides, Additional Nucleotide Products....
Biology Products: