The first component of the development award will be formal training in biochemistry, cellular biology, and physiology. This formal training will be augmented by professional interactions with clinical physicians and a mentored research effort in the development of near-infrared sensors for the monitoring of hemodialysis dose. The initial research component of this work will be the development of an all-optical sensor for the on-line measurement urea concentration in spent dialysate. An effective on-line urea sensor will allow regular, sample-free monitoring and optimization of hemodialysis dose. The sensor will also be adapted for measurements in the extracorporeal whole blood stream between the patient and the dialyzer. The measurement of urea in whole blood will provide a measurement of dose that is more directly related to current blood-based dose quantitation. Because near-infrared sensing technology permits simultaneous quantification of multiple analytes, the sensor will also be applied to quantification of other blood components, including serum albumin, serum creatinine, hematocrit, and uremic toxins, including hippuric acid and indoxyl sulfate. The capacity to monitor these additional analytes every dialysis session will be of substantial benefit to clinical physicians working with patients suffering from either end-stage or acute renal failure. Finally, the near- infrared sensor will be applied to non-invasive, in vivo measurements of urea in peripheral tissue sites. The information provided by such a measurement will be invaluable for the study of urea disequilibrium during dialysis and as a potentially rebound-free quantification of delivered dose. Initial instrument development will be performed in a laboratory environment using an in vitro model for sensor optimization. Calibration models will be generated for urea and other analytes. Sensor operation will then be validated in the clinical setting.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Mentored Quantitative Research Career Development Award (K25)
Project #
5K25DK002925-05
Application #
7030203
Study Section
Diabetes, Endocrinology and Metabolic Diseases B Subcommittee (DDK)
Program Officer
Rankin, Tracy L
Project Start
2002-05-01
Project End
2008-02-28
Budget Start
2006-03-01
Budget End
2008-02-28
Support Year
5
Fiscal Year
2006
Total Cost
$114,389
Indirect Cost
Name
University of Iowa
Department
Type
Organized Research Units
DUNS #
062761671
City
Iowa City
State
IA
Country
United States
Zip Code
52242
McCarthy, Ellen T; Sharma, Mukut; Savin, Virginia J (2010) Circulating permeability factors in idiopathic nephrotic syndrome and focal segmental glomerulosclerosis. Clin J Am Soc Nephrol 5:2115-21
Cho, David S; Olesberg, Jonathon T; Flanigan, Michael J et al. (2008) On-line near-infrared spectrometer to monitor urea removal in real time during hemodialysis. Appl Spectrosc 62:866-72
Olesberg, Jonathon T; Liu, Lingzhi; Van Zee, Valerie et al. (2006) In vivo near-infrared spectroscopy of rat skin tissue with varying blood glucose levels. Anal Chem 78:215-23
Olesberg, Jonathon T; Arnold, Mark A; Mermelstein, Carmen et al. (2005) Tunable laser diode system for noninvasive blood glucose measurements. Appl Spectrosc 59:1480-4