A new filter that accurately mimics the solar UV-B spectrum using standard UV lamps: the photochemical properties, stabilization and use of the urate anion liquid filter.
The physiological effects unique to solar ultraviolet (UV)-B exposure (280-315 nm) are difficult to accurately replicate in the laboratory. This study evaluates the effectiveness of the sodium urate anion in a liquid filter that yields a spectrum nearly indistinguishable from the solar UV-B spectrum while filtering the emissions of widely used UV-B lamps. The photochemical properties and stability of this filter are examined and weighed against a typical spectrum of ground-level solar UV-B radiation. To test the effectiveness of this filter, light-saturated photosynthetic oxygen evolution rates were measured following exposure to UV-B filtered either by this urate filter or the widely used cellulose acetate (CA) filter. The ubiquitous marine Chlorophyte alga Dunaliella tertiolecta was tested under identical UV-B flux densities coupled with ecologically realistic fluxes of UV-A and visible radiation for 6 and 12 h exposures. These results indicate that the urate-filtered UV-B radiation yields minor photosynthetic inhibition when compared with exposures lacking in UV-B. This is in agreement with published experiments using solar radiation. In sharp contrast, radiation filtered by CA filters produced large inhibition of photosynthesis.
Sampath-Wiley
Priya
P
Department of Biological Sciences, University of New Hampshire, Durham, NH 03824, USA.
Jahnke
Leland S
LS
D000975:Antioxidants / Q000737:chemistry; D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry; D000460:Chlorophyta / Q000737:chemistry* / Q000254:growth & development / Q000528:radiation effects*; D005374:Filtration / Q000295:instrumentation*; D007202:Indicators and Reagents; D010084:Oxidation-Reduction; D010782:Photolysis; D010788:Photosynthesis / Q000528:radiation effects; D019810:Sodium Azide / Q000737:chemistry; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet; D014466:Ultraviolet Rays; D014527:Uric Acid / Q000737:chemistry*
D000975:Antioxidants; D007202:Indicators and Reagents; D012996:Solutions; D014527:Uric Acid; C005062:acetylcellulose; D002482:Cellulose; D019810:Sodium Azide