Navigation Links
Singlet Oxygen measurement


Introduction
The chemistry, spectroscopy, and reactivity of singlet oxygen, 1O2, is of considerable interest in environmental applications, novel organic syntheses and mechanisms of photo-oxygenation.1 Recently, research has been directed towards understanding the biological effects of 1O2, such as the photodynamic destruction of cells in the presence of a dye, oxygen, and light.

An understanding of the mechanisms that produce 1O2 is required for the synthesis of new anti-cancer agents used in photodynamic therapy. The spectroscopic properties of the dye and 1O2 may be characterized using fluorescence spectroscopy. The emission of 1O2 is in the near-IR, around 1280 nm. The SPEX FLUOROLOGsystem easily detects this signal, with the appropriate emission gratings and a suitable detector. Most multi-alkali photomultiplier tubes, such as the R928P, respond to wavelengths up to 800 nm. InGaAs detectors extend this range to nearly 1700 nm.

The SPEX DSS-IGA020L InGaAs detector is an excellent choice for 1O2 measurements. It operates at liquid-nitrogen temperature to minimize thermal noise. Usable from 8001700 nm, the InGaAs detector provides a smooth overlap with the standard R928P photomultiplier tube.


Experiment and Results
As an example of 1O2 detection, generated using a transition-metal complex, a solution of tris2-2-bipyridine ruthenium(II) chloride, [Ru(bpy)3]Cl2, in D2O, was used as a generator of 1O2.2 The optical density of the solution was 0.3 A above the D2O baseline at 450 nm. To enhance the yield of 1O2, the solution was saturated with O2 by bubbling the solution with pure oxygen for 5 min before measurement. The excitation maximum of the [Ru(bpy)3]2+ complex is in the visible region of the spectrum, near 450 nm.

A FLUOROLOG system, equipped with a 450-W xenon lamp, single-grating excitation and emission monochromators, and near-IR accessories (DSS-IGA020L InGaAs detector and emission grating at 600 grooves mm1, blazed at 1000 nm) was used to measure the 1O2 emission spectrum. A high-pass filter (λ = 780 nm) was used as an order-sorter, necessary when such large wavelength ranges are spanned. Figure 1 shows the emission spectrum obtained using an integration time of 0.1 s and a bandpass of 12 nm. The excellent signal-to-noise ratio is seen in the graph.


1 Wasserman, H.H.; Murray, R.W., in Singlet Oxygen; Academic Press: New York, 1979.
2
Mulazzani, et. al. J. Phys. Chem. 1994, 98, 1145.


back to top


'"/>

Source:


Page: All 1 2

Related biology technology :

1. Analysis of Fuel Oxygenates by U.S. EPA Method 8260B Using Headspace Trap with GC/MS
2. Quantitative end-point RT-PCR gene expression measurement using the Agilent 2100 Bioanalyzer and standardized RT-PCR
3. The measurement of DNA condensation and mitochondrial changes during apoptosis and necrosis in cell based assays
4. Utilization of Donkey Anti-Rabbit PS SPA Imaging Beads in the quantitative measurement of cAMP in cells
5. measurement of green fluorescent proteins and a red fluorescent protein in live cells in the Analyst GT multimode reader
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:3/22/2017)... The global chronic kidney disease ... by Transparency Market Research (TMR). The top four players, ... Inc., accounted for a share of only 41.4% in ... market are focusing aggressively on mergers, acquisitions, and strategic ... to lead to market consolidation in the next few ...
(Date:3/22/2017)... ... ... Premier executive recruitment firm, Slone Partners, is proud to have been named a Top ... Hunt Scanlon Media is one of the most respected life science publications in the ... sector. , “It is a great honor for Slone Partners to be part of ...
(Date:3/22/2017)... , ... March 21, 2017 , ... The Conference Forum ... (CMO Summit) to be held on May 10-11, 2017, at the Colonnade Hotel in ... specifically for Chief Medical Officer peer-to-peer learning, benchmarking and support. , “The Chief Medical ...
(Date:3/22/2017)... Israel , March 22, 2017  BrainStorm ... adult stem cell technologies for neurodegenerative diseases, announced today ... provide an update on new developments and a corporate ... Biopartnering and Investment Forum, being held on March 27 ... Neuroscience Biopartnering ...
Breaking Biology Technology:
(Date:2/16/2017)... , Feb. 16, 2017  Genos, a ... announced that it has received Laboratory Accreditation from ... Accreditation is presented to laboratories that meet stringent ... demonstrate scientifically rigorous processes. "Genos is ... in laboratory practices. We,re honored to be receiving ...
(Date:2/13/2017)... 13, 2017 Former 9/11 Commission border counsel ... Janice Kephart of Identity Strategy Partners, LLP, ... Trump,s "Executive Order: Protecting the Nation From Foreign ... "As President Trump,s ,Travel Ban, Executive Order ... essentially banned the travel ban, it is important that ...
(Date:2/8/2017)... About Voice Recognition Biometrics Voice recognition biometrics ... a stored voiceprint template. Acoustic features of an ... are compared to distinguish between individual voices. Voice ... PCs already have a microphone and can authenticate ... are most likely to be deployed in telephone-based ...
Breaking Biology News(10 mins):