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Evaluate the effects of light with Electron Paramagnetic Resonance (EPR)

Photochemistry plays an important role in many chemical processes. Irradiating a sample with a suitable wavelength of light often results in free radicals, radical pairs, excited states, and changes of oxidation state.
This webinar took place on March 19th 2019

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Photochemistry plays an important role in many chemical processes. Irradiating a sample with a suitable wavelength of light often results in free radicals, radical pairs, excited states, and changes of oxidation state.

Electron Paramagnetic Resonance (EPR) is the best technique for shedding light on these reactions and processes because of its unique ability to unambiguously detect paramagnetic species in a direct and non-intrusive manner.

EPR identifies the reaction intermediates as well as quantifies their concentrations, thus elucidating the reaction mechanisms and kinetics of photochemical reactions. It can be applied to samples in gaseous, liquid or sold states over a wide range of temperatures.

What you will discover

What attendees will learn:
Various applications of EPR spectroscopy in the field of photochemistry:

  • Measuring the extent of photodegradation after light exposure with EPR in polymers, food and beverages, pharmaceuticals, health care products, paint, environmental pollutants, etc.
  • Monitoring photochemical (photocatalysis and photopolymerization) reactions for understanding electron transfer mechanisms using EPR
  • Photoaging and reactive oxygen species detection by EPR: impact on human health

Who should attend?

  • General and R&D managers involved in QC/QA of product degradation, environment protection
  • Academics who do photochemical research or collaborate with companies to study photochemical processes
  • Researchers who study the effect of photodegradation reactions on human health


Dr. Kalina Ranguelova
Dr. Kalina Ranguelova
Senior EPR Applications Scientist, Bruker BioSpin
Dr. Kalina Ranguelova is an EPR Applications Scientist in Bruker BioSpin Corporation since 2011. She completed her Ph.D. at The Bulgarian Academy of Sciences where she received a Ph.D. with research focused on inorganic copper complexes structure using electron paramagnetic resonance (EPR) spectroscopy. After two research positions at CUNY and National Institute for Environmental Sciences where she studied free radical biology and EPR spin trapping as method for measurement of reactive oxygen species (ROS), she joined Bruker and holds a role as Applications Scientist. Her current focus is detection and identification of free radicals in biological systems and pharmaceuticals using spin traps and spin probes. She has publications in journals like Journal of Biological Chemistry, Biochemistry, Free radical Biology and Medicine, etc. She has presented in many international meetings related to free radical research in biology and protein chemistry.
Dr. Ralph Weber
Dr. Ralph Weber
Senior EPR Applications Scientist, Bruker BioSpin
Dr. Ralph Weber started his scientific training at Brown University where he received a B.A in Chemistry and German Literature and Language. He continued his training at the University of Chicago, earning a Ph.D. in chemistry focusing on EPR and ENDOR studies of proteins and lanthanide complexes. Two postdoctoral positions followed. At Leiden University in the Netherlands he studied excited states of molecules using ODMR (Optically Detected Magnetic Resonance) and designed and constructed a high frequency pulse EPR spectrometer. At MIT he studied motional dynamics in lipids via solid state NMR and was one of the original project members to design and construct a DNP (Dynamic Nuclear Polarization) spectrometer incorporating a high power gyrotron. He joined Bruker 29 years ago in 1989. He is responsible for much of the documentation for EPR and also offers customer support for pulse, high frequency, and imaging applications. He is currently co-principal investigator on a five-year NIH grant to develop pre-clinical EPR imaging technology and to promote its use in the pharmaceutical industry.