Human VEGF165b ELISA Kit

**Human VEGF165b ELISA Kit – For the Quantitative In Vitro Determination of Human Vascular Endothelial Growth Factor 165b Concentrations in Serum, Plasma, Cerebrospinal Fluid, Tissue Homogenate, and Other Body Fluids** *For Laboratory Research Use Only. Not for Diagnostic or Therapeutic Procedures.* This ELISA kit is designed for the quantitative measurement of Human VEGF165b in various biological samples. The procedure involves a colorimetric reaction where the optical density (OD) at 450 nm is measured using a spectrophotometer. The Stop Solution changes the color from blue to yellow, allowing for accurate quantification. The kit includes a set of calibration standards that are run alongside the samples to generate a standard curve. This curve is used to determine the concentration of VEGF165b in the unknown samples by comparing their OD values to the standard curve. **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 centrifuging at 2000×g for 20 minutes. Remove the serum and assay immediately, or aliquot and store at -20°C. Avoid repeated freeze-thaw cycles. - **Plasma:** Collect plasma using heparin as an anticoagulant. Centrifuge within 30 minutes of collection at 2000×g for 30 minutes at 2–8°C. Store at -20°C. Avoid repeated freeze-thaw cycles. - **Cell Culture Supernatants, Tissue Homogenates, and Other Biological Fluids:** Centrifuge to remove particulates and assay immediately or store at -20°C. Ensure no hemolysis or granules are present in the samples. **Materials Required but Not Supplied:** - 37°C incubator - Microplate reader capable of measuring absorbance at 450 nm - Precision pipettes, disposable tips, and absorbent paper - Distilled or deionized water **Reagents Provided (Stored at 2–8°C):** - Microtiter Strip Plate (12×8 strips / 12×4 strips) - Standard (6 vials, 0.5 ml/vial) - Sample Diluent (6.0 ml / 3.0 ml) - HRP-Conjugate Reagent (10.0 ml / 5.0 ml) - 20X Wash Solution (25 ml / 15 ml) - Chromogen Solution A (6.0 ml / 3.0 ml) - Chromogen Solution B (6.0 ml / 3.0 ml) - Stop Solution (6.0 ml / 3.0 ml) - Closure Plate Membrane (2 units) - User Manual (1 copy) - Sealed Bags (1 unit) **Standard Concentrations:** 2400, 1200, 600, 300, 150, 75 pg/mL. If sample values exceed the highest standard, dilute with Sample Diluent and repeat the assay. **Precautions:** - Do not mix reagents from different kit lots. All components are calibrated for optimal performance. - Allow all reagents to reach room temperature (20–25°C) before use. Do not thaw samples or reagents using a water bath. - Do not use reagents past their expiration date. - Use only deionized or distilled water for dilutions. - Keep microtiter plates in sealed bags until needed. Unused strips should be stored with desiccant at 2–8°C. - Wear gloves during the procedure. Handle all biological samples as potentially infectious. - Dispose of all samples and waste following proper biohazard protocols. - Substrate solution must be free of contamination. If it appears bluish, discard it. - Chromogen B contains 20% acetone; keep away from heat or flame. **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. Run standards and samples in duplicate. 2. Add 50 µl of standard or sample to each well. Do not add anything to the blank well. 3. Add 100 µl of HRP-Conjugate Reagent to all wells except the blank. Cover with an adhesive strip and incubate for 60 minutes at 37°C. 4. Wash the plate 4 times. Manual washing: aspirate contents, fill with wash solution, and repeat. Automated washing: aspirate and wash four times with 350 µL/well. 5. Add 50 µl of Chromogen A and 50 µl of Chromogen B to each well. Incubate for 15 minutes at 37°C, protected from light. 6. Add 50 µl of Stop Solution. The color will change from blue to yellow. If uneven, gently tap the plate. 7. Read OD at 450 nm. Generate a standard curve by plotting average OD vs. concentration. 8. Calculate mean OD for each standard and sample. Subtract blank OD from all values. 9. Determine sample concentrations by intersecting OD with the standard curve. 10. Each user should create their own standard curve. Intra- and inter-assay CVs are <15%. **Assay Range:** 75 pg/mL – 2400 pg/mL **Sensitivity:** <10 pg/mL **Cross-Reactivity:** No significant cross-reactivity with other proteins. **Storage:** 2–8°C (frequent use); -20°C (long-term storage). **Shelf Life:** 6 months at -20°C. **Note:** Always follow the manufacturer’s instructions and safety guidelines when handling biological materials. This kit is not intended for diagnostic use.

Lighter Automatic Typesetting Machine

lighter, lighter assembly line, lighter typesetting machine, lighter assembly equipment, lighter machines

GuangDong Feetoo Automation Technology Co., Ltd. , https://www.feetoolighter.com