Navigation Links
Time gated separation of lanthanide luminescence


Introduction
The distinctive luminescence of lanthanide ions has long been a challenge for the spectroscopist. Methods to counter the extremely low absorption coefficients and luminescence quantum yields have concentrated on
Protective ligands to reduce vibrational quenching effects by XH moieties (X = O, N,).
Deuterated solvents (also to reduce quenching effects of XH).
Antenna chromophores for enhanced absorption (with later energy-transfer to, and luminescence by, the lanthanide).

Luminescence from these systems comprises a number of sharp and well-resolved bands with characteristically long lifetimes, roughly 106 103 s, depending upon the degree of quenching. With an integrated phosphorimeter, the SpexFluoroMax-P allows convenient time-gated measurement of lanthanide systems. In this Application Note, two lanthanide complexes comprising an encapsulating complex with benzophenone antenna chromophore (L, see Fig. 1) and europium (Eu) or terbium (Tb) ions are investigated using time-gated spectroscopy with the FluoroMax-P.


Experiment & Results
An excitation source (xenon lamp) flashes (~ 3 s pulse-width). Detection of the samples luminescence occurs within a time-window after the flash, according to a chosen delay time and detection-window size. Acquisition of a spectrum corresponding to any desired time-slice during the luminescence decay is possible. Luminescence lifetime measurements are made by recording the intensity of a specific wavelength with a chosen detection-window size and incremented delay time (Fig. 2).


The individual spectra of Tb-L and Eu-L complexes are shown in Figs. 3 and 4. The resulting luminescence spectrum from a mixture of Tb-L and Eu-L (Fig. 5) combines features from both Tb-L and Eu-L, acquired with a delay time of 0.01 ms, and sample window of 10 ms. Thus results from detection of all the luminescence from both species appear in Fig. 5. Time-gating allows a mixture of the two species to be spectrally separated, based on their different lifetimes (~ 0.60 ms for Eu-L, and ~ 1.1 ms for Tb-L).




Careful choice of gating parameters allows spectra from this mixture to be obtained selectively from an early time (to minimize Tb-L and maximize Eu-L) and a late time (with negligible Eu-L, approximating pure Tb-L), as shown in Fig. 6. A time-gated matrix scan (Fig. 7) shows the dependence of the spectral profile with time. A number of complete emission spectra were recorded while automatically incrementing the delay time between each run. The result is a 3-D array, with intensity, wavelength, and time information.



Conclusions
The Spex FluoroMax-P spectrofluorometer with integral flash-lamp can perform time-gated spectroscopic separation of mixtures of chemical species.


Acknowledgements
We thank Drs. Andrew Beeby and Gareth Williams of the Chemistry Department, University of Durham, UK, for useful discussion and preparation of the compounds studied herein.


back to top


'"/>

Source:


Page: All 1 2

Related biology technology :

1. Performance of the AMARA HitHunter Chemiluminescence Kinase Assay with the LEADseeker Multimodality Imaging System
2. Use of BRET2 luminescence cell-based assays with LEADseeker Multimodality Imaging System
3. Photoluminescence Spectroscopy of Quantum Dots, monitored by the Spex FluoroMax
4. A highly sensitive ATP-luminescence assay using VICTOR2 with the dispenser option
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:10/9/2017)... N.C. (PRWEB) , ... October 09, 2017 , ... At ... announced Dr. Christopher Stubbs, a professor in Harvard University’s Departments of Physics and Astronomy, ... Stubbs was a member of the winning team for the 2015 Breakthrough Prize in ...
(Date:10/7/2017)... Phoenix, Arizona (PRWEB) , ... ... ... than 15 years’ experience providing advanced instruments and applications consulting for microscopy ... the in-house expertise in application consulting, Nanoscience Analytical offers a broad range ...
(Date:10/6/2017)... ... October 06, 2017 , ... The HealthTech Venture Network (HTVN) ... their fourth annual Conference where founders, investors, innovative practitioners and collaborators are invited ... competition showcasing early stage digital health and med tech companies. , This day-long ...
(Date:10/5/2017)... ... October 05, 2017 , ... Understanding the microbiome, the millions of bacteria ... Gut Love: You Are My Future, the newest exhibit on display at the University ... the human condition through the lens of the gut microbiome. , Gut Love ...
Breaking Biology Technology:
(Date:4/11/2017)... April 11, 2017 Crossmatch®, a globally-recognized ... solutions, today announced that it has been awarded ... Projects Activity (IARPA) to develop next-generation Presentation Attack ... "Innovation has been a driving force within ... will allow us to innovate and develop new ...
(Date:4/11/2017)... N.Y. , April 11, 2017 ... fingerprints, but researchers at the New York University ... College of Engineering have found that partial similarities ... security systems used in mobile phones and other ... thought. The vulnerability lies in the ...
(Date:4/6/2017)... April 6, 2017 Forecasts by ... Document Readers, by End-Use (Transportation & Logistics, Government & ... Gas & Fossil Generation Facility, Nuclear Power), Industrial, Retail, ... Are you looking for a definitive report ... ...
Breaking Biology News(10 mins):