EU FullyFunded Access to the Free Radical Research Facility at Daresbury

1
EU Fully-Funded Access to the Free Radical
Research Facility at Daresbury
R Edge1,2, DJ Holder3, S Navaratnam1,4 and RH
Bisby4. 1. FRRF_at_Daresbury. 2. North East Wales
Institute. 3. ASTeC, Daresbury Laboratory. 4.
University of Salford.
Introduction

• Time-resolved resonance Raman spectroscopy (TR3)
  - pulsed laser system synchronised with either
  linac pulses or NdYAG laser pulses.
• Confocal microscopy - Pulsed titanium sapphire
  laser - maximum scan speed of 1 frame/second.
• Time-resolved detection systems - optical
  absorption and emission, conductivity, resonance
  Raman at variable temperatures (77K - 350K).
• Single wavelength and multiple wavelength
  detection systems.
• Fully staffed for complete service.
• Fully equipped support laboratories.
• EU funding provides access to users from the
  European
• Union and Associated states (see website).

This is a new facility at Daresbury Laboratory,
comprising of the complementary techniques of
pulse radiolysis, laser flash photolysis, ESR,
Confocal microscopy, time-resolved resonance
Raman spectroscopy, time-resolved luminescence
spectroscopy to study free radicals and excited
states of biologically important molecules.
Free radicals

• In biology, free radicals are frequently
  implicated in disease
• In motor neurone disease, for example, a mutant
  form of the enzyme superoxide dismutase, which
  normally protects against free radical damage,
  becomes a potent source of damaging hydroxyl
  radicals.
• In heart disease (atherosclerosis), free
  radicals lead to the oxidation of fats in the
  blood and hence to the formation of
  artery-blocking plaques.
• Protection is available from natural
  antioxidants, such as vitamins E and C,
  flavonoids and carotenoids, which intercept
  damaging free radicals.
• In chemistry, the damaging effects of free
  radicals are experienced by the nuclear industry.
  Ionising radiation produces free radicals which
• Degrade polymers,
• Decompose solvents (including aqueous systems)
• Not all free radicals are bad news however, as
  some may also be beneficial
• Radiotherapy induces free radicals which destroy
  cancerous cells.
• Blood pressure is regulated by the action of
  nitric oxide, a relatively long-lived free
  radical.
• Photosynthesis involves free radicals.
• Some drugs exert their effects by free-radical
  mechanisms.

The Facility

• Pulse radiolysis - 12 MeV electron linac
  provides single or multiple (up to 10 Hz) pulses
  of electrons.
• Fully-calibrated digital control of pulse length
  in the range 220ns to 2.2µs - doses up to 20
  Grays per shot.
• Laser flash photolysis - NdYAG laser - 15ns
  266nm, 355nm and 532nm pulses, up to 500mJ.

Current EU Funded Research
1. Radical scavenging and triplet excited state
properties of eight regio-isomers of
pyrrolidine bis adduct derivatives of
C60. 2. Dynamic behaviour of triplet states and
charge carriers in conjugated organic
polymers. 3. Involvement of reactive
intermediates in the oxidative degradation of
lignin and lignin model compounds. Generation and
reactivity of ketyl radicals, alkoxyl radicals
and aromatic radical cations. 4. Photoionizaton
of alpha-tocopherol and related molecules
identification of the primary photoproducts
and probing the fate of the radical
cation. 5. Determination of the function of
tyrosinase-related protein 1 (TRP1) in the
regulation of melanogenesis. 6. Determination of
the Efficiency of Oxidizing Radicals to Interact
with Plasmenylcholine. 7. Properties of
protein radicals and protein peroxyl radicals and
their reactions. 8. Pulse radiolysis of the
pesticide metsulfuron and aromatic sulfonic
acid derivatives. 9. Photophysical properties of
C59N fullerenes. 10. Radical scavenging
properties of seven water-soluble
cyclodextrin- C60 conjugates. 11. Formation
and reactions of free radicals derived from
photosensitized oxygenations.
The pulse radiolysis line in the SRS Linac Hall
at Daresbury.
www.frrf.dl.ac.uk
Contact S. Navaratnam, FRRF, E6 Daresbury
Laboratory, Warrington, WA4 4AD, UK. Tel. 44
1925 603721 Fax. [phone] E-mail.
s.navaratnam_at_dl.ac.uk