Technical Information

The most accurate method to measure glomerular filtration rate (GFR) is to track the renal clearance of an ideal filtration marker (1).  An ideal filtration marker is freely cleared through the glomerulus, is not reabsorbed and does not bind to serum proteins.  BioPAL has labeled such an agent with a stable isotope to provide researchers with an easy-to-use and nonradioactive method to measure GFR.  This innovative, patent pending product-line is called RenalRate™ and consists of a metal chelated by diethylenetriaminepentaacetic acid (DTPA).  The product is autoclaved and ready-to-use. RenalRate an be purchased labeled with one of three different stable isotopes: samarium, lutetium, and europium.  This product-line provides researchers with the opportunity to obtain a second or third GFR measurement within a short period of time of the first measurement unlike conventional radioactive GFR compounds.   RenalRate therefore, provides the opportunity to obtain a second GFR measurement in the event of a misadministration of the first injection.

RenalRate is designed for use as a single injection, however the product can support most protocols to measure GFR.  RenalRate is used in the same manner as traditional radioactive markers, such as ⁵¹Cr-EDTA (2-5) except that the assay of the stable-isotope labeled marker is performed by BioPAL.   At the end of the in vivo phase of the experiment, blood and/or urine samples are collected and placed in BioPAL's tracer-free polypropylene sample vials and sent to BioPAL for neutron activation analysis to measure the concentration of GFR marker content.  The true measurement of GFR offers a superior end-point in renal drug development studies, as compared to estimating renal function by evaluating biomarkers, such as serum creatinine, cystatin-C, microalbumin, etc., that are influenced by non-renal factors.

Development of this product line has, in part, been supported by National Institutes of Health (NIH) Small Business Innovation Research (SBIR) grants sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases.  See What's New!

New Immunoassay Technology to Measure GFR!  In addition to neutron activation technology, BioPAL has also developed an alternative method to accurately measure GFR based on Functional Immunoassay Technology (FIT).  To learn more, click on FIT-GFR.

Important - NOT FOR HUMAN USE.

References

1. Kidney Int 52, S144 (1997)
2. Scand J Clin Lab Invest 36, 35 (1976)
3. Am J Kidney Dis 16, 224 (1990)
4. Eur J Nucl Med 22, 532 (1995)
5. J Nucl Med 39, 2131 (1998)

The Product

1. GFR reagent
   RenalRate is a complex of DTPA and is ready-to-use.  The reagent is offered labeled with one of three different stable isotopes and is packaged in a 20 mL vial.  The recommended dose is 0.4 ml/kg. (Patent Pending)
   Download a PDF price list.
   Download a PDF MSDS.
   Download a PDF general protocol information.
    
2. Contaminant-Free, Sample Vials
   BioPAL's polypropylene sample vials are cleaned to remove trace contamination and are calibrated for our activation and counting system.  These vials must be used for the assay.
   Download a PDF price list.
    
3. Assay Service
   BioPAL charges a per-sample assay fee.  The results of the assay are reported as the total disintegrations per minute (dpm) measured in each sample for each corresponding stable isotope label.  For an additional charge, BioPAL will calculate the GFR value.
   Download a PDF price list.
   Download a PDF Assay Request Form.

Highlights

RenalRate™ can be used to measure or detect:

• Glomerular filtration rate (GFR)
• Membrane permeability
• Brain hemorrhage

Advantages

• No radioactivity
• No hazardous reagents
• Non-destructive assay procedure
• Low cost
• High sensitivity and specificity
• Three different labels
• Three GFR measurements within a short period of time
• Archive the original samples
• The ability to re-assay samples
• Fast experimental turnover time

Request for Additional Information and Pricing