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J Med Toxicol. Mar 2010; 6(1): 35–36.
Published online Mar 13, 2010. doi:  10.1007/s13181-010-0033-6
PMCID: PMC2861174
The Poison Pen: Bedside Diagnosis of Urinary Diquat
Rais Vohra,corresponding author Anthony Salazar, F. L. Cantrell, Ravindra Fernando, and Richard F. Clark
Department of Emergency Medicine, UCSF-Fresno Medical Center, 155 N. Fresno Drive, Fresno, CA 93701 USA
University of California, San Diego, CA USA
California Poison Control System, San Diego, CA USA
National Hospital, Colombo, Sri Lanka
Rais Vohra, Phone: +1-818-3643107, Fax: +1-818-3643268, raisvohra/at/
corresponding authorCorresponding author.
Diquat is a bipyridyl herbicide with nephrotoxic effects. This in vitro study demonstrates a colorimetric test for detection of diquat in human urine. Urine specimens using ten concentrations of diquat herbicide solution and controls for urine and glyphosate were prepared. A two-step assay (addition of bicarbonate followed by sodium dithionite) was performed, with a resulting color change of the original solution for each specimen. Color change intensity was noted immediately and after 30 min, by gross visual inspection. A green color with concentration-dependent intensity was detected in all specimens, in which concentrations of diquat solution ranged from 0.73 to 730 mg/L. This colorimetric effect disappeared after 30 min. The sodium bicarbonate/dithionite test may be useful as a qualitative bedside technique for the detection of urinary diquat in the appropriate clinical setting.
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Selected References
These references are in PubMed. This may not be the complete list of references from this article.
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