A portable fiberoptic ratiometric fluorescence analyzer provides rapid point-of-care determination of glomerular filtration rate in large animals

Exing Wang, Daniel J. Meier, Ruben M. Sandoval, Vanessa E. Von Hendy-Willson, Barrak M. Pressler, Robert M. Bunch, Mouhamad Alloosh, Michael S. Sturek, George J. Schwartz, Bruce A. Molitoris

Research output: Contribution to journalArticle

50 Scopus citations


Measurement of the glomerular filtration rate (GFR) is the gold standard for precise assessment of kidney function. A rapid, point-of-care determination of the GFR may provide advantages in the clinical setting over currently available assays. Here we demonstrate a proof of principle for such an approach in a pig and dogs, two species that approximate the vascular access and GFR results expected in humans. In both animal models, a sub-millimeter optical fiber that delivered excitation light and collected fluorescent emissions was inserted into a peripheral vein (dog) or central venous access (pig) by means of commercial intravenous catheters. A mixture of fluorescent chimeras of a small freely filterable reporter and large non-filterable plasma volume marker were infused as a bolus, excited by light-emitting diodes, and the in vivo signals detected and quantified by photomultiplier tubes in both species in less than 60 min. Concurrent standardized 6-h iohexol plasma kidney clearances validated the accuracy of our results for both physiologic and a chronic kidney disease setting. Thus, our ratiometric technique allows for both measurement of plasma vascular volume and highly accurate real-time GFR determinations, enabling clinical decision making in real time.

Original languageEnglish (US)
Pages (from-to)112-117
Number of pages6
JournalKidney international
Issue number1
StatePublished - Jan 1 2012



  • acute kidney injury
  • chronic kidney disease
  • glomerular filtration rate

ASJC Scopus subject areas

  • Nephrology

Cite this