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:5/23/2017)... ... 23, 2017 , ... Energetiq Technology, a world leader in ... to accommodate its rapid growth. , The renovations at the company’s headquarters in ... existing areas. The expansion includes, a state-of-the-art engineering facility, and a second clean ...
(Date:5/23/2017)... ... May 23, 2017 , ... Cambridge Semantics , ... at this year’s Bio-IT World Conference and Expo in Boston May 23-25 ... 4.0 solution. The Anzo Smart Data Lake is also a finalist for the ...
(Date:5/22/2017)... (PRWEB) , ... May 22, 2017 , ... ... joined with other leaders of the Maryland Biohealth community in developing and issuing ... recognized Top 3 U.S. BioHealth Innovation Hub by 2023. , ...
(Date:5/21/2017)... ... May 20, 2017 , ... ... avoid the lengthy trial and error process by finding the right antidepressant faster. ... also strengthen the doctor-patient relationship through a personalized approach to treatment. ...
Breaking Biology Technology:
(Date:5/16/2017)...  Veratad Technologies, LLC ( www.veratad.com ), an innovative ... verification solutions, announced today they will participate as a ... thru May 17, 2017, in Washington D.C.,s ... Identity impacts the lives of billions ... evolving digital world, defining identity is critical to nearly ...
(Date:4/19/2017)... ALBANY, New York , April 19, 2017 /PRNewswire/ ... highly competitive, as its vendor landscape is marked by ... in the market is however held by five major ... and Safran. Together these companies accounted for nearly 61% ... majority of the leading companies in the global military ...
(Date:4/13/2017)... 2017 According to a new market research report ... Identity Administration, and Authorization), Service, Authentication Type, Deployment Mode, Vertical, and Region ... expected to grow from USD 14.30 Billion in 2017 to USD 31.75 ... ... MarketsandMarkets Logo ...
Breaking Biology News(10 mins):