Oxygen Availability in Polyethylene Glycol Solutions and Its Implications in Plant-Water Relations 1
AUTOR(ES)
Mexal, John
RESUMO
The solubility of O2 in polyethylene glycol 4000 and 6000 solutions of varying concentrations was determined iodimetrically (titrimetrically) and electrochemically using a rotating glassy carbon electrode and a PAR Model 174 Polarograph. The titrimetric determination resulted in the formation of an unexpected precipitate at 2% (w/v) polyethylene glycol corresponding to the approximate critical micelle concentration of the two polyethylene glycol homologs. Beyond 5% polyethylene glycol, O2 concentration was inversely proportional to polyethylene glycol concentration, and was higher in polyethylene glycol 4000 solutions than in polyethylene glycol 6000. The electrochemical data are a direct measure of O2 transport to the electrode surface, rather than O2 activity or concentration. Results indicate that even at relatively high H2O potentials, the transport of O2 to the root surface might be insufficient to meet the plant's respiratory requirements.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=541543Documentos Relacionados
- Root Growth and Oxygen Relations at Low Water Potentials. Impact of Oxygen Availability in Polyethylene Glycol Solutions1
- In vitro antibacterial activity of concentrated polyethylene glycol 400 solutions.
- Water Potential of Aqueous Polyethylene Glycol
- A comparative X-ray diffraction and circular dichroism study of DNA compact particles formed in water-salt solutions, containing poly(ethylene glycol).
- Relationship between Salt Tolerance and Resistance to Polyethylene Glycol-Induced Water Stress in Cultured Citrus Cells 1
