**Human DKK4 ELISA Kit – For the quantitative in vitro determination of Human Dickkopf 4 concentrations in serum, plasma, cerebrospinal fluid, tissue homogenate, and other body fluids. Intended for laboratory research use only. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE.**
Before using this kit, please read the entire package insert carefully. This ELISA (Enzyme-Linked Immunosorbent Assay) is designed to measure the concentration of DKK4 in various biological samples through a competitive binding mechanism.
The test works by detecting the presence of DKK4 in the sample, which binds to specific antibodies coated on the microplate. After incubation, a horseradish peroxidase (HRP)-conjugated detection antibody is added. A chromogenic substrate is then used to produce a color change, which is proportional to the amount of DKK4 present. The reaction is stopped with a stop solution, and the optical density (OD) is measured at 450 nm using a microplate reader. By comparing the OD values of the unknown samples to a standard curve, the DKK4 concentration can be accurately determined.
**Sample Collection and Storage:**
- **Serum:** Use a serum separator tube. Allow samples to clot for 2 hours at room temperature or overnight at 4°C before centrifugation at 2000×g for 20 minutes. Assay immediately or aliquot and store at -20°C. Avoid repeated freeze-thaw cycles.
- **Plasma:** Collect using heparin as an anticoagulant. Centrifuge within 30 minutes at 2000×g and 2–8°C. Store at -20°C. Avoid repeated freezing.
- **Cell culture supernatants, tissue homogenates, and other body fluids:** Centrifuge to remove particulates. Assay immediately or store at -20°C. Ensure no hemolysis or granules are present.
**Materials Required (Not Supplied):**
1. Incubator set at 37°C
2. Microplate reader capable of measuring absorbance at 450 nm
3. Pipettes, disposable tips, and absorbent paper
4. Distilled or deionized water
**Reagents Provided (Stored at 2–8°C):**
- Microtiter Strip Plate (12×8 or 12×4 strips)
- Standard (6 vials, 0.5 mL/vial) – concentrations: 80, 40, 20, 10, 5, 2.5 ng/mL
- Sample Diluent (6.0 mL or 3.0 mL)
- HRP-Conjugate Reagent (10.0 mL or 5.0 mL)
- 20X Wash Solution (25 mL or 15 mL)
- Chromogen Solution A (6.0 mL or 3.0 mL)
- Chromogen Solution B (6.0 mL or 3.0 mL)
- Stop Solution (6.0 mL or 3.0 mL)
- Closure Plate Membrane (2 pieces)
- User Manual
- Sealed Bags (1 each)
**Important Notes:**
- Do not use reagents beyond their expiration date.
- Always allow reagents and samples to reach room temperature (20–25°C) before use.
- Do not thaw reagents in a water bath.
- Use only deionized or distilled water for dilutions.
- Keep all kit components sealed until needed.
- Store unused strips in their pouch with desiccant at 2–8°C.
- Use fresh pipette tips for each transfer to prevent cross-contamination.
- Substrate B contains 20% acetone; keep away from heat or flame.
- If the chromogen appears bluish before use, discard it.
- Waste containing biological materials should be treated with sodium hypochlorite (final concentration 1.0%) for at least 30 minutes before disposal.
**Reagent Preparation:**
- Wash Solution (1X): Dilute 1 volume of 20X Wash Solution with 19 volumes of deionized or distilled water. Store at 2–8°C for up to one month.
**Assay Procedure:**
1. Prepare all reagents before starting.
2. Add 100 µL of standards, samples, and blanks to the microplate wells.
3. Cover with adhesive strips and incubate for 60 minutes at 37°C.
4. Wash the plate 4 times manually or using an automated washer.
5. Add 50 µL of Chromogen A and 50 µL of Chromogen B to each well. Incubate for 15 minutes at 37°C, protecting from light.
6. Add 50 µL of Stop Solution to each well. Read OD at 450 nm within 15 minutes.
**Calculation:**
- Plot average OD values against standard concentrations.
- Subtract blank OD from all measurements.
- Use graph paper or software to generate a standard curve.
- Determine sample concentration by interpolation.
**Performance Characteristics:**
- Sensitivity: <1.0 ng/mL
- Intra-assay CV: <10%
- Inter-assay CV: <15%
- No significant cross-reactivity with other proteins
**Storage:**
- Store unopened kit at 2–8°C for frequent use, or at -20°C for long-term storage (up to 6 months).
**Note:** This product is intended for research purposes only and should not be used in diagnostic procedures. Always follow proper safety protocols when handling biological samples and reagents.
Complex Pu Sponge,Daily Use Products For Kitchen,Dual Sided Cleaning Spong,Dual Sided Clean Sponges
Puyang Maikefu Commodity Co., LTD , https://www.maikefufoam.com