| Field | Specification |
|---|---|
| Mfr No | |
| Assay Time | |
| Detection Method | |
| Product Type | |
| Sample Type(s) | Urea in biological samples (e.g. plasma, serum, urine, bronchoalveolar lavage (BAL)) and food/beverage samples (e.g. milk) |
| Shipping | |
| Species | |
| Storage |
Overview
For quantitative enzymatic determination of urea. The assay uses OD340nm for signal readout. Compatible sample input includes Urea in biological samples (e.g. plasma, serum, urine, bronchoalveolar lavage (BAL)) and food/beverage samples (e.g. milk). Typical stated assay timing is 30 min.
Key elements and design rationale
- Readout format: OD340nm supports plate-based signal acquisition and consistent comparison across matched samples.
- Sample compatibility: The stated sample scope includes Urea in biological samples (e.g. plasma, serum, urine, bronchoalveolar lavage (BAL)) and food/beverage samples (e.g. milk), which is useful when aligning matrix type with calibration and control design.
- Analytical range context: The supplied specifications include a stated detection limit of 50 µM for interpreting low-signal samples.
- Feature emphasis: Fast and sensitive. Linear detection range (20 µL sample): 50 to 1000 µM urea in 96-well plate assay.
Additional feature notes highlight Convenient. The procedure involves adding a single working reagent, and reading the absorbance after 30 minutes. Room temperature assay. No 37°C heater is needed; High-throughput. Homogeneous “mix-incubate-measure” type assay.Can be readily automated as a high-throughput 96-well plate assay for thousands of samples per day. Available format information for this listing includes 100 Tests.
Biological background
This product is centered on measurement of urea within the matrices described for the assay. In practice, datasets from this type of format are typically interpreted by comparing relative signal, activity, or abundance across matched control and experimental groups rather than relying on a single value in isolation. Careful alignment of sample matrix, incubation window, and calibration strategy is important when comparing results across plates, operators, or study days.
More details
UREA, the major end product of protein catabolism in animals, is primarily produced in the liver and secreted by the kidneys. It is the primary vehicle for removal of toxic ammonia from the body. Urea determination is very useful for medical clinicians to assess kidney function of patients. In general, increased urea levels are associated with nephritis, renal ischemia, urinary tract obstruction, and certain extrarenal diseases (e.g. congestive heart failure, liver diseases, and diabetes). Decreased levels often indicate acute hepatic insufficiency, but may also result from over vigorous parenteral fluid therapy. Simple, direct and automation-ready procedures for measuring urea or blood urea nitrogen (BUN) are popular in research and drug discovery.BioAssay Systems urea assay is designed to directly measure urea in biological samples. In this assay, urease converts urea to ammonia and carbon dioxide. NADH is then converted to NAD+ in the presence of ammonia, α-ketoglutarate, and glutamate dehydrogenase. The decrease in optical density at 340 nm is directly proportional to the urea concentration in the sample.
Detection method
Colorimetric (OD 340 nm).
Detection limit and analytical sensitivity
Reported detection limit: 50 µM.
Procedures and timing
Stated procedure or timing information: 30 min.
Research relevance and current trends
- Plate-based quantification and side-by-side group comparison remain central use cases for this assay format.
- The product notes emphasize multi-sample throughput, making it relevant for screening-oriented and larger batch comparison studies.
- Short assay timing and plate compatibility support time-course or repeated-measure collection plans when handling is kept consistent.
Common research applications
- Quantify urea in urea in biological samples (plasma, serum by OD340 nm readout.
- Compare treatment or phenotype groups using matched urea in biological samples (plasma, serum handling.
- Monitor time-course or pre/post changes in urea in biological samples (plasma, serum across study conditions.
Interpretation is usually strongest when signal changes are assessed alongside matrix-matched controls, replicate agreement, and the assay's stated analytical window.
Notes for experimental interpretation
- Matrix composition, background signal, and sample handling can influence apparent response; compare like-with-like whenever possible.
- Use appropriate blanks, controls, and replicate wells to distinguish biological differences from plate, reagent, or handling variability.
How do I store the kit?
This kit is shipped on ice. Upon receiving, please store the kit at -20°C. Urease can be stored at -20°C to 4°C.
Can I store unused reagents for future use?
Yes, unused reagents can be stored according to the assay protocol. Repeated freeze/thaw cycles of reagents should be avoided. The dried NADH Reagent is stable for 3 weeks after reconstitution.
Does glutamate in the sample interfere with the assay?
High glutamate concentrations (> 2 mM) will interfere with the assay. For example a typical concentration of glutamate in cell culture medium is ~0.15 mM.
I do not see any color change in my wells. Is the assay not working?
This assay measures the decrease in OD at 340 nm and the color change is not visible to the naked eye.
For laboratories requiring additional technical capacity, we provide scientific support services including assay execution, method guidance, product sourcing, and customization to align the assay with specific experimental objectives. If you need assistance selecting the appropriate kit configuration, adapting the workflow to your application, or identifying related research services, please click Talk to a Scientist, email support@biohippo.com, or review our Research Services; a member of our scientific team will follow up with recommendations tailored to your study.
Prevalence of sublingual varices in patients with cirrhosis and the correlation with nitrogen compounds
Duarte, N. T. et al (2020). Prevalence of sublingual varices in patients with cirrhosis and the correlation with nitrogen compounds. Oral surgery, oral medicine, oral pathology and oral radiology, 129(1), 39-44. Assay: urea in human saliva and blood.