Retinol Binding Protein (RBP) Urine
The DetectX® Urinary Retinol Binding Protein (RBP) kit is designed to measure RBP present in urine samples.
The DetectX® Urinary Retinol Binding Protein (RBP) kit is designed to measure RBP present in urine samples. Please read the complete kit insert before performing this assay. A RBP standard is provided to generate a standard curve for the assay and all samples should be read off the standard curve. Standards or diluted samples are pipetted into a clear microtiter plate coated with an antibody to capture rabbit antibodies. A RBP-peroxidase conjugate is added to the standards and samples in the wells. The binding reaction is initiated by the addition of the RBP polyclonal antibody to each well. After an hour incubation the plate is washed and substrate is added. The substrate reacts with the bound RBPperoxidase conjugate. After a short incubation, the reaction is stopped and the intensity of the generated color is detected in a microtiter plate reader capable of measuring 450 nm wavelength. The concentration of the RBP in the sample is calculated, after making a suitable correction for the dilution of the sample, using software available with most plate readers
- Use the plate layout sheet on the back page of the kit insert to aid in proper sample and standard identification. Determine the number of wells to be used and return unused wells to foil pouch with desiccant. Seal the ziploc plate bag and store at 4°C.
- Pipet 50 µL of samples or standards into wells in the plate. Pipet 75 µL of Assay Buffer into the non-specific binding (NSB) wells. Pipet 50 µL of Assay Buffer into wells to act as maximum binding wells (Bo).
- Add 25 µL of the DetectX® RBP-peroxidase conjugate to each well, using a repeater pipet.
- Add 25 µL of the DetectX® RBP Antibody solution to each well, except the NSB wells, using a repeater pipet.
- Gently tap the sides of the plate to ensure adequate mixing of the reagents. Cover the plate with the plate sealer and shake at room temperature for 1 hour.
- Aspirate the plate and wash each well 4 times with 300 µL wash buffer. Tap the plate dry on clean absorbent towels.
- Add 100 µL of the TMB Substrate to each well, using a repeater pipet.
- Incubate the plate at room temperature for 30 minutes without shaking.
- Add 100 µL of the Stop Solution to each well, using a repeater pipet.
- Read the optical density generated from each well in a plate reader capable of reading at 450 nm.
- Use the plate reader’s built-in 4PLC software capabilities to calculate RBP concentration for each sample.
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