ELISA Genie Technical Manual. 8-epi-PGF2α / 8-Epi-Prostaglandin F2 Alpha ELISA Kit

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Transcription:

ELISA Genie Technical Manual 8-epi-PGF2α / 8-Epi-Prostaglandin F2 Alpha ELISA Kit Catalogue Code: UNFI0037 Research Use Only 1

1. Description and Principle 2. Key Features and Sample Types 3. Workflow Overview 4. Kit Contents 5. Shipping and Storage 6. Sample preparation 7. Protocol 8. Data Analysis 9. Important General Notes 1. Description and Principle The 8-epi-PGF2α / 8-Epi-Prostaglandin F2 Alpha ELISA Kit can assay for 8-epi-PGF2α / 8-Epi- Prostaglandin F2 Alpha in the following samples: serum, blood, plasma, cell culture supernatant and other related supernatants and tissues. How our 8-epi-PGF2α / 8-Epi-Prostaglandin F2 Alpha ELISA Kits Work? The ELISA Genie ELISA (enzyme-linked immunosorbent assays) assay kits are designed for the quantitative measurement of analytes in a wide variety of samples. As today s scientists demand high quality consistent data for high impact journals, We have developed a range of sensitive, fast and reliable ELISA kit assays to meet and exceed those demands. 2

2. Key features and Sample Types Aliases: 8-epi-PGF2α Detection method: Competitive Range: 15.625-1000pg/ml Sensitivity: 9.375pg/ml 3

3. Workflow Overview Prepare reagents, samples and standards and equilibrate to room temperature Wash plate x2 and aspirate off all liquid Add 100µL standard, sample or blank to wells Incubate @ 37⁰C for 90 minutes Remove the liquid. Add 100µL Biotin-detection antibody work solution Incubate @ 37⁰C for 60 minutes Wash plate x 3 Add 100µL SABC working solution Wash plate x 5 Incubate @ 37⁰C for 30 minutes Add 90µL TMB Substrate Solution Add 50µl Stop solution to each well Incubate @ 37⁰C for 15-30 minutes Measure OD @ 450nm 4

4. Kit Contents Product Size Cat. Code 8-epi-PGF2α / 8-Epi-Prostaglandin F2 Alpha ELISA Kit 96 assays UNFI0037 Each kit contains reagents for 96 assays in a 96 well plate including: No. Component Qty No. Component Qty 1 Standard 2 vials 7 HRP-Streptavidin Conjugate (SABC) 120µl 2 Biotin-detection Sample/Standard Dilution 20ml 8 antibody buffer (Concentrated) 120µl 3 ELISA Strip plate coated with monoclonal antibodies 12w 8s 9 Stop Solution 10ml 4 Wash Buffer (25 ) 30ml 10 TMB Substrate 10ml 5 SABC dilution buffer 10ml 11 Plate Sealer 5 pieces 6 Antibody dilution buffer 10ml 12 Manual 1 Additional Materials required 1. 37⁰C incubator 2. Plate shaker 3. Plate Reader with 450nm filter 4. Precision pipettes and disposable pipette tips 5. Distilled water 6. Disposable tubes for sample dilution 7. Absorbent paper 5. Shipping and Storage Store kit @ 4⁰C for 6 months 5

6. Sample Preparation General considerations: extract samples as soon as possible after specimen collection. According to best practices, experiments should be carried out as soon as possible after the extraction. Alternatively, extract can be kept at -20⁰C but for optimal results, avoid repeated freeze-thaw cycles. Samples that contain NaN3 cannot be detected as it interferes with HRP. Serum: Use a serum separator tube (SST) and allow samples to clot for 30 minutes before centrifugation for 15 minutes at approximately 1000 g. Remove serum and assay immediately or aliquot and store samples at -20⁰C or -80⁰C. Plasma: Collect plasma using EDTA or heparin as an anticoagulant. Centrifuge samples for 15 minutes at 1000 g at 2⁰C - 8⁰C within 30 minutes of collection. Store samples at -20⁰C or -80⁰C. Avoid repeated freeze-thaw cycles. Note: over hemolyzed samples are not suitable for use with this kit. Urine: collect in a sterile container, centrifuge for 20 mins @ 2000-3000 rpm. Remove supernatant and if any precipitation is detected repeat centrifugation step. A similar protocol can be used for cerebrospinal fluid. Cell culture supernatant: collect supernatant and centrifuge @ 4⁰C for 20 mins @ 2000-3000 rpm. Remove supernatant and rinse cells x2 times with PBS (ph 7.2-7.4) and perform a total cell count. Optimal cell concentration is 1 million / ml. To release cellular components, dilute the cell pellet in PBS and use 3-4 freeze-thaw cycles in liquid Nitrogen (commercial lyses buffers can be used according to manufacturer s instructions). Centrifuge @ 4⁰C for 20 mins @ 2000-3000 rpm to pellet debris and remove clear supernatant to clean microcentrifuge tube for ELISA or storage. Tissue samples: the preparation of tissue homogenates will vary depending upon tissue type. For this assay, tissue was rinsed with 1X PBS to remove excess blood, homogenized in 20mL of 1X PBS and stored overnight at -20⁰C 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 supernatant and assay immediately or aliquot and store at -20⁰C. Notes: 1. Samples to be used within 5 days may be stored at 2-8⁰C, otherwise samples must be stored at - 20⁰C (1 month) or -80⁰C (2 months) to avoid loss of bioactivity and contamination. 2. Tissue or cell extraction samples prepared by chemical lysis buffer may cause unexpected ELISA results due to the impacts of certain chemicals. 3. Influenced by the factors including cell viability, cell number and also sampling time, samples from cell culture supernatant may not be detected by the kit 4. Sample hemolysis will influence the result, so hemolytic specimen cannot be detected. 5. When performing the assay slowly bring samples to room temperature. 6

7. Protocol Manual Washing Discard the solution in the plate without touching the side walls. Clap the plate on absorbent filter papers or other absorbent material. Fill each well completely with 350ulwash buffer and soak for 1 to 2 minutes, then aspirate contents from the plate, and clap the plate on absorbent filter papers or other absorbent material. Repeat this procedure two more times for a total of THREE washes. Automated Washing Aspirate all wells, then wash plate THREE times with 350ul wash buffer. After the final wash, invert plate, and clap the plate on absorbent filter papers or other absorbent material. It is recommended that the washer be set for a soaking time of 1 minute. Sample Collection and Storage Isolate the test samples soon after collecting, then, analyze immediately (within 2 hours). Or aliquot and store at -20 Cfor long term. Avoid multiple freeze-thaw cycles. Serum: Allow samples to clot for 2 hours at room temperature or overnight at 4 Cbefore centrifugation for 20 minutes at approximately 1000 g. Collect the supernatant and carry out the assay immediately. Blood collection tubes should be disposable, non-pyrogenic, and nonendotoxin. Plasma: Collect plasma using EDTA-Na2 as an anticoagulant. Centrifuge samples for 15 minutes at 1000 g at 2-8 Cwithin 30 minutes of collection. Collect the supernatant and carry out the assay immediately. Avoid hemolysis, high cholesterol samples. Tissue homogenates: For general information, hemolysis blood may affect the result, so you should rinse the tissues with ice-cold PBS (0.01M, ph=7.4) to remove excess blood thoroughly. Tissue pieces should be weighed and then minced to small pieces which will be homogenized in PBS (the volume depends on the weight of the tissue. 9mL PBS would be appropriate to 1 gram tissue pieces. Some protease inhibitor is recommended to add into the PBS.) with a glass homogenizer on ice. To further break the cells, you can sonicate the suspension with an ultrasonic cell disrupter or subject it to freeze-thaw cycles. The homogenates are then centrifugated for 5minutes at 5000 g to get the supernatant. Cell culture supernatant: Centrifuge supernatant for 20 minutes to remove insoluble impurity and cell debris at 1000 g at 2-8 C. Collect the clear supernatant and carry out the assay immediately. Other biological fluids: Centrifuge samples for 20 minutes at 1000 g at 2-8 C. Collect the supernatant and carry out the assay immediately. Sample preparation: Samples should be clear and transparent and be centrifuged to remove suspended solids. Note: 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 contamination. Hemolyzed samples are not suitable for use in this assay. Sample Dilution Guideline Reagent Preparation and Storage Bring all reagents to room temperature before use. 1. Wash Buffer: Dilute 30mL of Concentrated Wash Buffer into 750 ml of Wash Buffer with deionized or distilled water. Put unused solution back at 4 C. If crystals have formed in the concentrate, you can warm it 7

with 40 Cwater bath (Heating temperature should not exceed 50 C) and mix it gently until the crystals have completely dissolved. The solution should be cooled to room temperature before use. 2. Standard: 1) 1000pg/ml of standard solution: Add 1 ml of Sample / Standard dilution buffer into one Standard tube, keep the tube at room temperature for 10 min and mix thoroughly. 2) 500pg/m --> 15.625pg/ml of standard solutions: Label 6 Eppendorf tubes with500pg/ml, 250pg/ml, 125pg/ml, 62.5pg/ml, 31.25pg/ml, 15.625pg/ml, respectively. Aliquot 0.3 ml of the Sample / Standard dilution buffer into each tube. Add 0.3 ml of the above1000pg/ml standard solution into 1st tube and mix thoroughly. Transfer 0.3 ml from 1st tube to 2nd tube and mix thoroughly. Transfer 0.3 ml from 2nd tube to 3rd tube and mix thoroughly, and so on. 0.3 ml 0.3 ml 0.3 ml 0.3 ml 0.3 ml 0.3 ml Blank 500 250 125 62.5 pg/ml 31.25 15.625 1000 Note: The standard solutions are best used within 2 hours. The standard solution should be at 4 C for up to 12 hours. Or store at -20 C for up to 48 hours. Avoid repeated freeze-thaw cycles. 3. Preparation of Biotin- detection Antibody working solution Prepare within 1 hour before the experiment. 1) Calculate the total volume of the working solution: 0.05 ml / well quantity of wells. (Allow 0.1-0.2 ml more than the total volume) 2) Dilute the Biotin-detection antibody with Antibody dilution buffer at 1:100 and mix thoroughly.(i.e. Add 1 µl of Biotin-detection antibody into 99 µl of Antibody dilution buffer.) 4. Preparation of HRP-Streptavidin Conjugate (SABC) working solution: Prepare within 30min before the experiment. 1) Calculate the total volume of the working solution: 0.1 ml / well quantity of wells. (Allow 0.1-0.2 ml more than the total volume) 2) Dilute the SABC with SABC dilution buffer at 1:100 and mix thoroughly. (i.e. Add 1 µl of SABC into 99 µl of SABC dilution buffer.) 8

Assay Procedure Before adding to wells, equilibrate the SABC working solution and TMB substrate for at least 30 min at 37 C. When diluting samples and reagents, they must be mixed completely and evenly. It is recommended to plot a standard curve for each test. 1. Set standard, test sample and control (zero) wells on the pre-coated plate respectively, and then, record their positions. It is recommended to measure each standard and sample in duplicate. Wash plate 2 times before adding standard, sample and control (zero) wells! 2. Add Sample and Biotin-detection antibody: Add 50µL of Standard, Blank, or Sample per well. The blank well is added with Sample / Standard dilution buffer. Immediately add 50 µl of Biotindetection antibody working solution to each well. Cover with the Plate sealer we provided. Gently tap the plate to ensure thorough mixing. Incubate for 45minutes at 37 C. (Solutions are added to the bottom of micro ELISA plate well, avoid inside wall touching and foaming to the best of your ability.) 3. Wash: Aspirate each well and wash, repeating the process three times Wash by filling each well with Wash Buffer (approximately 350µL) using a squirt bottle, multi-channel pipette, manifold dispenser or automated washer. 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 pat it against thick clean absorbent paper. 4. HRP-Streptavidin Conjugate(SABC): Add 100µL of SABC working solution to each well. Cover with a new Plate sealer. Incubate for 30minutes at 37 C. 5. Wash: Repeat the aspiration/wash process for five times. 6. TMB Substrate: Add 90µL of TMB Substrate to each well. Cover with a new Plate sealer. Incubate for about 15-20 minutes at 37 C. Protect from light. The reaction time can be shortened or extended according to the actual color change, but not more than 30minutes. When apparent gradient appeared in standard wells, you can terminate the reaction. 7. Stop: Add 50µL of Stop Solution to each well. Color turn to yellow immediately. The adding order of stop solution should be as the same as the substrate solution. 8. OD Measurement: Determine the optical density (OD Value) of each well at once, using a microplate reader set to 450 nm. You should open the microplate reader ahead, preheat theinstrument, and set the testing parameters. Calculation of results Average the duplicate readings for each standard and samples. Create a standard curve by plotting the mean OD Value for each standard on the y-axis or x-axis against the concentration on the x-axis or y-axis and draw a best fit curve through the points on the graph. It is recommended to use some professional software to do this calculation, such as curve expert 1.3 or 1.4. In the software interface, a best fitting equation of standard curve will be calculated using OD Value and concentrations of standard sample. The software will calculate the concentration of samples after entering the OD Value of samples. Also, you can enter the corresponding fitting equation and OD Value of samples into Excel to get the concentration of samples. If samples have been diluted, the concentration calculated from the standard curve must be multiplied by the dilution factor. If the OD of the sample surpasses the upper limit of the standard curve, you should re-test it after appropriate dilution. The actual concentration is the calculated concentration multiplied dilution factor. Recommended to use professional software curve expert to 1.3,for details, please visit: www.fntest.com. 9

Summary 1. Wash plate 2 times before adding standard, sample and control (zero) wells. 2. Add 50µL standard or sample to each well. 3. Immediately Add 50µL Biotin-detection antibody to each well. 4. Incubate for 45 minutes at 37 C. 5. Aspirate and wash 3 times. 6. Add 100µL SABC working solution to each well. Incubate for 30 minutes at 37 C. 7. Aspirate and wash 5 times. 8. Add 90µL TMB Substrate. Incubate 15-20 minutes at 37 C. 9. Add 50µL Stop Solution. Read at 450nm immediately. 10. Calculation of results Typical Data & Standard Curve Results of a typical standard run of a 8-epi-PGF2? ELISA Kit are shown below. This standard curve was generated at our lab for demonstration purpose only. Each user should obtain their own standard curve as per experiment. (N/A=not applicable) X pg/ml 0 15.625 31.25 62.5 125 250 500 1000 Y OD450 1.819 1.32 0.776 0.518 0.257 0.15 0.086 0.05 Specificity This assay has high sensitivity and excellent specificity for detection of 8-epi-PGF2?. No significant cross-reactivity or interference between 8-epi-PGF2? and analogues was observed. 10

Note: Limited by current skills and knowledge, it is impossible for us to complete the cross- reactivity detection between 8-epi-PGF2? and all the analogues, therefore, cross reaction may still exist. Recovery Matrices listed below were spiked with certain level of 8-epi-PGF2? and the recovery rates were calculated by comparing the measured value to the expected amount of 8-epi-PGF2? in samples. Matrix Recovery range (%) Average(%) serum(n=5) 90-99 95 EDTA plasma(n=5) 85-101 94 heparin plasma(n=5) 86-95 91 Linearity The linearity of the kit was assayed by testing samples spiked with appropriate concentration of 8- epi-pgf2? and their serial dilutions. The results were demonstrated by the percentage of calculated concentration to the expected. Sample 1:2 1:4 1:8 1:16 serum(n=5) 94-100% 92-104% 85-94% 91-102% EDTA plasma(n=5) 87-94% 90-101% 85-100% 86-98% heparin plasma(n=5) 89-100% 85-98% 80-100% 82-96% Precision Intra-assay Precision (Precision within an assay): 3 samples with low, middle and high level 8-epi- PGF2? were tested 20 times on one plate, respectively. Inter-assay Precision (Precision between assays): 3 samples with low, middle and high level 8-epi- PGF2? were tested on 3 different plates, 8 replicates in each plate. CV (%) = SD/meanX100 Intra-Assay: CV<8% Inter-Assay: CV<10% Stability The stability of ELISA kit is determined by the loss rate of activity. The loss rate of this kit is less than 10% within the expiration date under appropriate storage condition. Standard (n=5) 37 C for 1 month 4 Cfor 6 months Average(%) 80 95-100 To minimize extra influence on the performance, operation procedures and lab conditions, especially room temperature, air humidity, incubator temperature should be strictly controlled. It is also strongly suggested that the whole assay is performed by the same operator from the beginning to the end. 11

9. Important General Notes 1. The final experimental results will be closely related to validity of the products, laboratory skills of the end-users and the experimental conditions. Please make sure that sufficient samples are available. 2. Kits from different batches may be a little different in detection range, sensitivity and color developing time. Please perform the experiment exactly according to the instructions. 3. There may be some foggy substance in the wells when the plate is opened at the first time. It will not have any effect on the final assay results. 4. Do not remove microtiter plate from the storage bag until needed. 5. A microtiter plate reader with a bandwidth of 10nm or less and an optical density range of 0-3 OD or greater at 450nm wavelength is acceptable for use in absorbance measurement. 6. Use fresh disposable pipette tips for each liquid transfer to avoid contamination. 7. Do not substitute reagents from one kit lot to another. Use only the reagents supplied by manufacturer. 8. In order to achieve reproducible results, the operation of every step in the assay should be controlled. Furthermore, a preliminary experiment before every assay for each batch is recommended. 9. Each kit has been strictly passed Q.C tested. However, results from end-users might be inconsistent with our in-house data due to some unexpected transportation conditions or different lab equipment. Intra-assay variance among kits from different batches might arise from aforementioned factors. Safety Precaution 1. The Stop Solution suggested for use with this kit is an acid solution. Wear eye, hand, face, and clothing protection when using this material. 12

Contact Details Dublin, Ireland Email: info@elisagenie.com Web: www.elisagenie.com Copyright 2017 ReagentBio, All Rights Reserved. All information / detail is correct at time of going to print. 13