EASYStep Pro Human C-Reactive Protein (CRP) ELISA Kit
For reference only. Please follow the manual included in your kit for instructions.
Catalog Number
RDEp-CRP-Hu
The EASYStep Pro Human C-Reactive Protein (CRP) ELISA Kit (RDEp-CRP-Hu) is an enzyme-linked immunosorbent assay for quantitative detection of CRP in Human samples. This kit uses the EASYStep Pro ELISA format for colorimetric detection of natural CRP in samples including serum and plasma. The kit is easy to use and comes with a pre-coated microplate and all necessary reagents and buffers. The standard curve generated in the experiment is used to calculate the concentration of CRP in samples. For research use only.
Product Specifications
Product Name
EASYStep Pro Human C-Reactive Protein (CRP) ELISA Kit
Catalog Number
RDEp-CRP-Hu
Detection Range
125-8000pg/mL
Sensitivity
52.1pg/mL
Species Reactivity
Human
Species
Homo sapiens Human
Assay Length
1.5 hours
Experimental Method
Sandwich
Detection Method
Colorimetric
Sample Type
serum and plasma
UniProtKB
P02741
Storage
2-8°C
Shelf Life
6 months
Synonyms
PTX1
Product Details
Intended Use
This kit is a sandwich enzyme immunoassay for in vitro quantitative determination of human CRP concentrations in serum and plasma.
Test Principle
This kit employs Sandwich-ELISA principle. The micro-ELISA plate provided in this kit has been pre-coated with an antibody specific to CRP. Samples (or Standards) and Horseradish Peroxidase (HRP) linked antibody specific for CRP are added to the micro-ELISA plate wells and incubated. CRP in samples (or standards) binds with the coated antibody and HRP linked detection antibody. Free components are washed away. The substrate solution is added to each well. Only those wells that contain CRP and HRP linked detection antibody will appear blue in color. The enzyme-substrate reaction is terminated by the addition of stop solution and the color turns yellow. The optical density (OD) is measured spectrophotometrically at a wavelength of 450 ± 2 nm. The OD value is proportional to the concentration of CRP. You can calculate the concentration of CRP in the samples by comparing the OD of the samples to the standard curve.
Application Data
Reagents and Materials Provided
| Reagents | Size | Quantity |
|---|---|---|
| Micro ELISA Plate (Detachable) | 96T | 8 wells ×12 strips |
| 48T | 8 wells × 6 strips | |
| 24T | 8 wells × 3 strips | |
| 96T × 5 | 8 wells ×12 strips × 5 | |
| Reference Standard | 96T | 2 vials |
| 48T | 1 vial | |
| 24T | 1 vial | |
| 96T × 5 | 10 vials | |
| Detection Reagent Pro | 96T | 1 × 60 μL |
| 48T/24T | 1 × 30 μL | |
| 96T × 5 | 5 × 60 μL | |
| Diluent Buffer | 96T/48T/24T | 1 × 20 mL |
| 96T × 5 | 5 × 20 mL | |
| Detection Reagent Pro Diluent | 96T/48T/24T | 1 × 14 mL |
| 96T × 5 | 5 × 14 mL | |
| Wash Buffer (25×concentrate) | 96T/48T/24T | 1 × 30 mL |
| 96T × 5 | 5 × 30 mL | |
| Substrate Reagent | 96T/48T/24T | 1 × 10 mL |
| 96T × 5 | 5 × 10 mL | |
| Stop Solution | 96T/48T/24T | 1 × 10 mL |
| 96T × 5 | 5 × 10 mL | |
| Plate Sealer | 96T/48T/24T | 5 pieces |
| 96T × 5 | 25 pieces | |
| Instruction manual | 1 |
Materials Required but not Supplied
- Microplate reader with 450 ± 10 nm filter.
- Precision single or multi-channel pipettes and disposable tips.
- Eppendorf Tubes.
- Incubator capable of maintaining 37°C.
- Deionized or distilled water.
- Absorbent paper.
- Container for Wash Buffer.
Storage of the kits
- For unopened kits: All the reagents can be stored at 2-8°C for 6 months.
- For opened kits: Once the kit is opened, the remaining wells and reagents should be stored according to the table below. Data Table: Reagents | Storage conditions Micro ELISA Plate (Detachable) | 2-8°C, 1 month Reference Standard | 2-8°C, use the reconstituted standard within 24 hours Detection Reagent Pro | 2-8°C (Protect from light) Diluent Buffer | 2-8°C Detection Reagent Pro Diluent | Wash Buffer (25×concentrate) | Substrate Reagent | 2-8°C (Protect from light) Stop Solution | 2-8°C
- For the expiration date of the kit, please refer to the label on the kit box. All components are stable until this date.
- Return the unused wells to the foil pouch containing the desiccant pack and reseal along entire edge of zip-seal.
- It is highly recommended to use the remaining reagents within 1 month of opening.
Sample Collection and Storage
- Plasma - Collect plasma using EDTA-Na2 as an anticoagulant. Centrifuge samples for 15 minutes at 1000 × g at 2-8°C within 30 minutes of collection. Collect the supernatant for use in the assay. Hemolyzed samples are not suitable for use with this ELISA assay.
- Samples to be used within 5 days may be stored at 4°C, otherwise samples must be stored at -20°C (≤1 month) or -80°C (≤2 months) to avoid loss of bioactivity and/or contamination.
- Noticeable hemolysis will affect antibody-antigen reactions. Samples with any sign of hemolysis are not suitable for this assay.
- When performing the assay, bring samples to room temperature.
Reagent Preparation
- Bring all kit components and samples to room temperature (18-25°C) before use.
- Wash Solution - Dilute 30 mL of Wash Buffer (25×) with 720 mL of deionized or distilled water to prepare 750 mL of Wash Solution (1×).
- Standard - Centrifuge the standard at 10,000 × g for 1 minute. Add 1.0 mL of Diluent Buffer, let it stand for 10 minutes and invert it gently several times (not to foam). The concentration of the standard in the stock solution is 8000 pg/mL. Prepare 7 EP tubes containing 0.5 mL Diluent Buffer and use the diluted standard to produce a double dilution series according to the picture shown below. Mix each tube thoroughly before the next transfer. Prepare a dilution series with 7 points, for example: 8000 pg/mL, 4000 pg/mL, 2000 pg/mL, 1000 pg/mL, 500 pg/mL, 250 pg/mL, 125 pg/mL, and the last EP tube with Diluent Buffer is the blank at 0 ng/mL.
- Detection Reagent Pro working solution - Calculate the required amount before the experiment (50 μL/well). Prepare slightly more than necessary for your experiment. Centrifuge the Detection Reagent Pro at 800 × g for 1 minute, then dilute it to the working concentration with Detection Reagent Pro Diluent (1:100).
- Do not perform a serial dilution directly in the wells.
- Prepare standard within 15 minutes of performing the assay. Do not dissolve the reagents at 37°C directly.
- Carefully reconstitute Standards according to the instruction. To minimize imprecision caused by pipetting, use small volumes and ensure that pipettors are calibrated.
- The reconstituted Standards can be used only once.
- If crystals have formed in the Wash Buffer (25×), warm to room temperature and mix gently until the crystals are completely dissolved.
- Any contaminated water or container used during reagent preparation will influence the detection result.
Assay Procedure Summary
- Add 50 µL standard or sample to each well, immediately add add 50 μL of Detection Reagent Pro working solution to each well. Incubate for 60 minutes at 37°C.
- Aspirate and wash the plate for 5 times.
- Add 90 µL Substrate Solution. Incubate for 15 minutes at 37°C.
- Add 50 µL Stop Solution. Read at 450 nm immediately.
Calculation of Results
Average the duplicate readings for each standard, control and sample, then subtract the average zero standard optical density. Construct a standard curve by plotting the mean O.D. and concentration for each standard and draw a best fit curve through the points on the graph or create a standard curve on log-log graph paper with CRP concentration on the y-axis and absorbance on the x-axis. If samples have been diluted, the concentration read from the standard curve must be multiplied by the dilution factor.
Product Data
Sensitivity
- The minimum detectable dose of CRP is typically less than 52.1 pg/mL.
- The sensitivity of this assay, or Lower Limit of Detection (LLD) was defined as the lowest protein concentration that could be differentiated from zero. It was determined by adding two standard deviations to the mean optical density value of twenty zero standard replicates and calculating the corresponding concentration.
Specificity
- This assay has high sensitivity and excellent specificity for detection of human CRP.
- No significant cross-reactivity or interference between human CRP and analogs was observed.
- Limited by current skills and knowledge, it is impossible to perform all possible cross-reactivity detection tests between CRP and all analogs, therefore, cross reactivity may still exist.
Precision
- Intra-assay Precision (Precision within an assay): 3 samples with low, middle and high level CRP were tested 20 times on one plate, respectively.
- Inter-assay Precision (Precision between assays): 3 samples with low, middle and high level CRP were tested on 3 different plates, 8 replicates in each plate.
- CV (%) = SD/mean × 100
- Intra-Assay: CV<10%
- Inter-Assay: CV<12%
Stability
- The stability of ELISA kit is determined by the loss rate of activity. The loss rate of this kit is less than 5% within the expiration date under appropriate storage conditions.
- To minimize unnecessary influences on the performance, operation procedures and lab conditions, especially room temperature, air humidity, and incubator temperatures should be strictly regulated. It is also strongly suggested that the whole assay is performed by the same experimenter from the beginning to the end.