Future Directions and Concluding Remarks

Whilst homogeneous photochemical systems have both advantages and disadvantages, the main issues relate to low reduction rates, to the use of expensive 

1 Aresta, M. (ed.) (2003) Carbon Dioxide Recovery and Utilization, Kluwer Academic Publishers, Boston. 

9 Keene, F.R. and Sullivan, B.P. (1993) Electrochemical and Electrocatalytic Reactions of Carbon Dioxide (eds B.P. Sullivan, K. Krist, and H.E. Guard), Elsevier, Amsterdam, Ch 5. 

3 Song, C., Gaffney, A.M., and Fujimoto, K. (eds) (2002) C02 Conversion and Utilization, ACS Symposium Series 809, American Chemical Society, Washington, DC. 

The PHSS method of real-time H2S measurement allows for investigating the potentially complex H2S kinetic responses of organs, tissues, cells, and mitochondria as levels of O2 and NO as well as metabolic state are adjusted within physiological limits. Kinetic changes in H2S concentration continuously reported by the PHSS, which are not seen with other H2S measurement techniques, suggest potentially complex interactions of H2S production and consumption mechanisms. H2S may likely exist as a cellular pool of free and labile persulfides able to rapidly respond to redox challenges with production and consumption pathways that operate to maintain the pool. This possible scenario reinforces the need for the PHSS as a valuable tool to provide a continual report of H2S throughout the course of an experimental treatment or to accurately determine H2S levels in situ. 

This research is supported in part by the American Heart Association grant-in-aid 0455296B and NIGMS grant 08-RGM073049A to DWK and WPl R D research fund forXZ. 

Electrochemical Sensors, Biosensors and Their Biomedical Applications 

National Research Council. Committee on Medical and Biological Effects of Environmental Pollutants Subcommittee on Hydrogen Sulfide Hydrogen Sulfide. University Park Press, Baltimore, MD (1979). 

Shergill, W.-P. Lu, and A.P. Wood, Oxidative metabolism of inorganic sulfur compounds by bacteria. Antonie van Leeuwenhoek 71, 95-107 (1997). 

ABCC7 cystic fibrosis transmembrane conductance regulator 

ABCG2 ATP-binding cassette sub-family G member 2 breast cancer 

ARFY Atherosclerosis Risk Factors in Female Youngsters 

ATSDR Agency for Toxic Substance and Disease Registry 

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