AQP2 ELISA Kit

Catalog No. ABIN578762

Product Details AQP2 ELISA Kit

Target: AQP2 (Aquaporin 2 (Collecting Duct) (AQP2))

Reactivity: Rat

Detection Method: Colorimetric

Method Type: Sandwich ELISA

Detection Range: 0.312-20 ng/mL

Minimum Detection Limit: 0.312 ng/mL

Application: ELISA

Purpose: This immunoassay kit allows for the in vitro quantitative determination of rat Aquaporin 2, AQP-2 concentrations in urine and other biological fluids.

Sample Type: Urine

Analytical Method: Quantitative

Specificity: This assay recognizes recombinant and natural rat AQP-2.

Cross-Reactivity (Details): No significant cross-reactivity or interference was observed.

Sensitivity: The sensitivity of this assay, or Lower Limit of Detection (LLD) was defined as the lowest detectable concentration that could be differentiated from zero.

Characteristics: Rattus norvegicus,Rat,Aquaporin-2,AQP-2,ADH water channel,Aquaporin-CD,AQP-CD,Collecting duct water channel protein,WCH-CD,Water channel protein for renal collecting duct,Aqp2

Components: Reagent (Quantity ): Assay plate (1×20ml), 2 Standard (2), Sample Diluent (1 × 20ml), Assay Diluent A (1x10ml), Assay Diluent B (1x10ml), Detection Reagent A (1 × 120μl), Detection Reagent B (1 × 120μl), Wash Buffer (25 x concentrate) (1 × 30ml), Substrate (1x10ml), Stop Solution (1x10ml), Plate sealer for 96 wells (5), Instruction (1)

Material not included: Luminometer. Pipettes and pipette tips. EP tube Deionized or distilled water.

Application Details

Sample Volume: 100 μL

Plate: Pre-coated

Protocol: The microtiter plate provided in this kit has been pre-coated with an antibody specific to AQP-2. Standards or samples are then added to the appropriate microtiter plate wells with a biotin-conjugated polyclonal antibody preparation specific for AQP-2 and Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. Then a TMB substrate solution is added to each well. Only those wells that contain AQP-2, biotin-conjugated antibody and enzyme-conjugated Avidin will exhibit a change in color. The enzyme-substrate reaction is terminated by the addition of a sulphuric acid solution and the color change is measured spectrophotometrically at a wavelength of 450 nm ± 2 nm. The concentration of AQP-2 in the samples is then determined by comparing the O.D. of the samples to the standard curve.

Reagent Preparation:

Bring all reagents to room temperature before use. Wash Buffer - If crystals have formed in the concentrate, warm to room temperature and mix gently until the crystals have completely dissolved. Dilute 20 mL of Wash Buffer Concentrate into deionized or distilled water to prepare 500 mL of Wash Buffer. Standard - Reconstitute the Standard with 1.0 mL of Sample Diluent. This reconstitution produces a stock solution of 10 ng/mL. Allow the standard to sit for a minimum of 15 minutes with gentle agitation prior to making serial dilutions. The undiluted standard serves as the high standard (10 ng/mL). The Sample Diluent serves as the zero standard (0 ng/mL). Detection Reagent A and B - Dilute to the working concentration specified on the vial label using Assay Diluent A and B (1:100), respectively.

Sample Collection: Cell culture supernates - Remove particulates by centrifugation and assay immediately or aliquot and store samples at ≤ -20 °C. Avoid repeated freeze-thaw cycles. Serum - Use a serum separator tube (SST) and allow samples to clot for 30 minutes before centrifugation for 15 minutes at approximately 1000 x g. Remove serum and assay immediately or aliquot and store samples at -20 °C. Plasma - Collect plasma using EDTA or heparin as an anticoagulant. Centrifuge samples for 15 minutes at 1000 x g at 2 - 8 °C within 30 minutes of collection. Store samples at ≤ -20 °C. Avoid repeated freeze-thaw cycles. Note: Citrate plasma has not been validated for use in this assay. Tissue homogenates - The preparation of tissue homogenates will vary depending upon tissue type. For this assay, heart and lung tissue from eight mice or one rat was rinsed with 1X PBS to remove excess blood, homogenized in 20 mL of 1X PBS and stored overnight at ≤ -20 °C. After two freeze-thaw cycles were performed to break the cell membranes, the homogenates were centrifuged for 5 minutes at 5000 x g. Remove the supernate and assay immediately or aliquot and store at ≤ -20 °C.

Assay Procedure:

Allow all reagents to reach room temperature. Arrange and label required number of strips. 3
1. Prepare all reagents, working standards and samples as directed in the previous sections.
2. Add 100 uL of Standard, Control, or sample* per well. Cover with the adhesive strip. Incubate for 2 hours at 37 °C.
3. Remove the liquid of each well, don’t wash.
4. Add 100 uL of Detection Reagent A to each well. Incubate for 1 hour at 37°C. Detection Reagent A may appear cloudy. Warm to room temperature and mix gently until solution appears uniform.
5. Aspirate each well and wash, repeating the process three times for a total of three washes. Wash by filling each well with Wash Buffer (350 uL) using a squirt bottle, multi-channel pipette, manifold dispenser or autowasher. Complete removal of liquid at each step is essential to good performance. After the last wash, remove any remaining Wash Buffer by aspirating or decanting. Invert the plate and blot it against clean paper towels.
6. Add 100 uL of Detection Reagent B to each well. Cover with a new adhesive strip.Incubate for 1 hours at 37 °C.
7. Repeat the aspiration/wash as in step
5. 8. Add 90 uL of Substrate Solution to each well. Incubate for 30 minutes at room temperature. Protect from light.
9. Add 50 uL of Stop Solution to each well. If color change does not appear uniform, gently tap the plate to ensure thorough mixing.
10. Determine the optical density of each well within 30 minutes, using a microplate reader set to 450 nm.
Important Note:1. The wash procedure is critical. Insufficient washing will result in poor precision and falsely elevated absorbance readings.
2. It is recommended that no more than 32 wells be used for each assay run if manual pipetting is used since pipetting of all standards, specimens and controls should be completed within 5 minutes. A full plate of 96 wells may be used if automated pipetting is available.
3. Duplication of all standards and specimens, although not required, is recommended.
4. When mixing or reconstituting protein solutions, always avoid foaming.
5. To avoid cross-contamination, change pipette tips between additions of each standard level, between sample additions, and between reagent additions. Also, use separate reservoirs for each reagent.
6. To ensure accurate results, proper adhesion of plate sealers during incubation steps is necessary.

Calculation of Results:

Average the duplicate readings for each standard, control, and sample and subtract the average zero standard optical density. Create a standard curve by reducing the data using computer software capable of generating a four parameter logistic (4-PL) curve-fit. As an alternative, 4 construct a standard curve by plotting the mean absorbance for each standard on the y-axis against the concentration on the x-axis and draw a best fit curve through the points on the graph. The data may be linearized by plotting the log of the AQP1 concentrations versus the log of the O.D. and the best fit line can be determined by regression analysis. This procedure will produce an adequate but less precise fit of the data. If samples have been diluted, the concentration read from the standard curve must be multiplied by the dilution factor.

Restrictions: For Research Use only

Handling

Handling Advice: 1. The kit should not be used beyond the expiration date on the kit label.
2. Do not mix or substitute reagents with those from other lots or sources.
3. If samples generate values higher than the highest standard, further dilute the samples with the Assay Diluent and repeat the assay. Any variation in standard diluent, operator, pipetting technique, washing technique,incubation time or temperature, and kit age can cause variation in binding.
4. This assay is designed to eliminate interference by soluble receptors, ligands, binding proteins, and other factors present in biological samples. Until all factors have been tested in the Immunoassay, the possibility of interference cannot be excluded.

Storage: 4 °C/-20 °C

Storage Comment: The Standard, Detection Reagent A, Detection Reagent B and the 96-well strip plate should be stored at -20 °C upon being received. The other reagents can be stored at 4 °C.

Target Details for AQP2

Target: AQP2 (Aquaporin 2 (Collecting Duct) (AQP2))

Alternative Name: Aqp2 (AQP2 Products)

Synonyms: AQP-CD ELISA Kit, WCH-CD ELISA Kit, cph ELISA Kit, jpk ELISA Kit, AQP-2 ELISA Kit, aquaporin-2 ELISA Kit, aquaporin 2 ELISA Kit, aquaporin 2 (collecting duct) ELISA Kit, Aqp2 ELISA Kit, AQP2 ELISA Kit

Background: Transfer of water across the cellular membrane is mediated by water channel proteins named aquaporins (AQPs). More than 10 isoforms of AQPs have been identified in mammalian cells so far. AQP2 is expressed in the principal cells of the collecting ducts in the kidney and plays a critical role in the urine concentration. A unique feature of AQP2 is that it is stored in the intracellular compartment, and upon stimulation of an antidiuretic hormone (ADH, vasopressin), AQP2 translocates to the apical plasma membrane, where it serves in the uptake of water from the lumen of the collecting duct. The mutation of AQP2 leads to nephrogenic diabetes insipidus, the inability to concentrate urine. In the recessive nephrogenic diabetes insipidus, mutated AQP2 is retained in the endoplasmic reticulum, whereas in the dominant types, it is localized in the Golgi complex, lysosome, or basolateral plasma membrane. These findings clearly show the importance of proper localization and trafficking of AQP2 for its function.

Gene ID: 3116

Pathways: Response to Water Deprivation