Measurement of gaseous hydrogen peroxide with a liquid core waveguide chemiluminescence detector
2001; Elsevier BV; Volume: 442; Issue: 1 Linguagem: Inglês
10.1016/s0003-2670(01)01102-3
ISSN1873-4324
AutoresJianzhong Li, Purnendu Κ. Dasgupta,
Tópico(s)Water Quality Monitoring and Analysis
ResumoHydrogen peroxide is an important atmospheric oxidant that is photochemically produced. It is typically present in the atmosphere at low to sub-part per billion by volume (ppbv) levels. Typically, enzyme-mediated fluorogenic techniques are used for the sensitive measurement of H2O2. We present here a simple luminol chemiluminescence (CL) measurement of H2O2 with a liquid core waveguide (LCW)-based instrument. The LCW acts both as a reaction cell and a light collector and terminates in a conventional, high numerical aperture optical fiber that carries the CL emission to an inexpensive photomultiplier tube (PMT). Gaseous hydrogen peroxide is collected with a high efficiency Nafion membrane diffusion scrubber. The H2O2 in the scrubber effluent is quantified by Co(II)-catalyzed oxidation of alkaline luminol. The linear range is at least up to 100 ppbv H2O2. A limit of detection (LOD) of 25 pptv H2O2 is achieved with an inexpensive miniature photomultiplier tube (PMT). The interference equivalent ozone is ∼<0.5%. At typical ambient levels, NO2 and SO2 do not interfere.
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