Bio-Rad Bio-Plex Precision Pro Human Cytokine Assays User Manual

Requires Bio-Plex
Manager™ 4.1 software
(or later versions)
Bio Plex®Precision Pro
-
Cytokine Assay
Instruction Manual
For technical support, call your local Bio-Rad office or in the US, call 1-800-4BIORAD (1-800-424-6723).
For research use only. Not for diagnostic procedures.
Table of Contents
Section 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Section 2 Principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Section 3 Required Materials . . . . . . . . . . . . . . . . . . . . .4
Section 4 Recommended Materials . . . . . . . . . . . . . . . . 5
Section 5 Sample Preparation . . . . . . . . . . . . . . . . . . . . 6
Section 6 Standard Preparation . . . . . . . . . . . . . . . . . . . 7
Section 7 Control Preparation (Optional) . . . . . . . . . . . . 9
Section 8 Assay Instructions . . . . . . . . . . . . . . . . . . . . 10
Plan Experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Prepare Coupled Magnetic Beads . . . . . . . . . . . . . 11
Calibrate Vacuum
Assay Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Section 9 Data Acquisition . . . . . . . . . . . . . . . . . . . . . . 15
Apparatus . . . . . . . . . . . . . . . . . 11
Section 10 Troubleshooting
Section 11 Safety Considerations . . . . . . . . . . . . . . . . . .24
. . . . . . . . . . . . . . . . . . . . . . 20
Section 1 Introduction
Bio-Plex®Precision Pro™ cytokine assays are highly sensitive magnetic bead-based multiplex assays that allow the accurate measurement of low levels of cytokines in diverse matrices including serum, plasma, and culture supernatant. The multiplexing feature makes it possible to quantitate the level of multiple cytokines in a single well of a 96-well microplate in just 3 hr, using as little as 12.5 µl of serum or plasma, or 50 µl of culture supernatant.
As one of the most recent additions to the Bio-Plex suspension array system, these assays incorporate magnetic beads into their design. The magnetic beads allow the use of an assay protocol similar to non­magnetic Bio-Plex cytokine assays, with the option of using magnetic separation of wash steps instead of vacuum filtration (and allows automation of many of the steps). The 25-bead map in Bio-Plex Manager™ 4.1 software (or later versions) is required for data acquisition.
These assays are offered in a convenient kit format that includes assay, reagent, and diluent components in a single box. Standard diluents for serum and plasma are included, as are additional Iylophilized cytokines which can be used to prepare user-specified quality controls.
For a current listing of Bio-Plex Precision Pro cytokine assays, visit us on the Web at www.bio-rad.com/bio-plex/
1
Section 2 Principle
Technology
The Bio-Plex technologies. The first is a novel technology that uses up to 100 unique fluorescently dyed beads (xMAP technology) that permit the simultaneous detection of up to 100 different types of molecules in a single well of a 96-well microplate. The second is a flow cytometer with two lasers and associated optics to measure the different molecules bound to the surface of the beads. The third is a high-speed digital signal processor that efficiently manages the fluorescent output.
Assay Format
The principle of these 96-well plate-formatted, bead-based assays is similar to a captur desired target cytokine is covalently coupled to internally dyed beads. The coupled beads are allowed to react with a sample containing the target cytokine. After a series of washes to remove unbound protein, a biotinylated detection antibody specific for a different epitope is added to the reaction. The result is the formation of a sandwich of antibodies around the target cytokine. Streptavidin-phycoerythrin (streptavidin-PE) is then added to bind to the biotinylated detection antibodies on the bead surface.
Data Acquisition and Analysis
Data from the reaction are then acquired using the Bio-Plex suspension array system (or Luminex system), a dual-laser reader system. The contents of the well are drawn up into the reader. The lasers and associated optics detect the internal fluorescence of the individual dyed beads as well as the fluorescent signal on the bead surface. This identifies each assay and reports the level of target protein in the well. Intensity of fluorescence detected on the beads indicates the relative quantity of targeted molecules. A high speed-digital processor efficiently manages the data output, which is further analyzed and presented as fluorescence intensity on Bio-Plex Manager™ software, the accompanying software package.
2
®
suspension array system is built around three core
e sandwich immunoassay. An antibody directed against the
, flow-based microplate
Assay Workflow
Prewet wells
Add beads
Wash
Add standards, controls,
and samples, 1hr
Wash
Add detection antibody, 30 min
Wash
Add streptavidin-PE, 10 min
Wash
Resuspend, acquire data
3
Section 3
Coupled magnetic beads (25x) 1 vial
Detection antibodies (10x) 1 vial
Standard 2 vials
Control 1 vial
Standard diluent (serum) 10 ml
Standard diluent (plasma) 10 ml
Sample diluent 15 ml
Assay buffer 75 ml
Wash buffer 150 ml
Detection antibody diluent 15 ml
Streptavidin-PE (100x) 1 vial
Sterile filter plate (96-well) 1 plate
Sealing tape 1 pack of 4
Component Units
Required Materials
Bio-Plex®Precision Pro™ assays are offered in a convenient kit format that includes assay, reagent, and diluent components all in a single box (does not require separate reagent and diluent kits). These assays require the use of Bio-Plex Manager™ software version 4.1 or higher.
Storage and Stability
Kit components should be stored at 4ºC and should never be frozen. Coupled magnetic beads and str dark. All components are guaranteed for up to 6 months from the date of purchase when stored as specified in this manual.
4
eptavidin-PE should be stored in the
Section 4
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Pipets and pipet tips, sterile distilled water, aluminum foil, absorbent paper towels, 1.5 ml microcentrifuge tubes, 15 ml culture tubes
Recommended Materials
For optimal results, the use of the items below is recommended.
5
Section 5 Sample Preparation
This section provides instructions for preparing samples derived from serum, plasma, and culture supernatant. For sample preparations not mentioned here, consult the publications listed in Bio-Rad bulletin 5297, available for download at discover.bio-rad.com
Serum and Plasma Samples
Note that for plasma samples, EDTA tubes are recommended; however, sodium citrate tubes ar filtered with a 0.22 µm filter to prevent clogging. Hemolyzed samples are not suitable for Bio-Plex
1. Collect and process the serum or plasma samples and assay immediately or freeze at –20ºC. Avoid repeat freezing and thawing.
2. Centrifuge the samples at 13,200 rpm for 10 min at 4ºC to clear the samples of precipitate. Alternatively, carefully filter the samples with a 0.22 µm filter to prevent instrument clogging.
3. Immediately dilute 1 volume of sample with 3 volumes of sample diluent. Keep the samples on ice until ready for use.
Culture Supernatant Samples
1. Collect and process the culture supernatant samples and assay
immediately or fr
e acceptable. Extremely lipemic samples may be
®
Precision Pro™ cytokine assays.
eeze at –20ºC. Avoid repeat freezing and thawing.
2. If required, dilute the culture supernatant with culture medium.
Serum-free culture medium should contain carrier protein (such as BSA) at a concentration of at least 0.5%. Keep the samples on ice until ready for use.
6
Section 6
Serum Serum standard diluent
Plasma Plasma standard diluent
Culture supernatant Same culture medium used
to prepare samples
Sample Standard Diluent
Standard Preparation
Two tubes of Iyophilized cytokine standard are provided in each Bio-Plex Precision Pro™ cytokine assay. However, only one of the tubes is required per 96-well plate. The product insert provided with the assay lists the concentration of the reconstituted standard. This procedure will prepare enough standard to run each dilution in duplicate.
Reconstitute Standards
1. Gently tap the glass vial containing the lyophilized cytokine standard on a solid surface to ensur
2. Reconstitute 1 vial of lyophilized standard with 500 µl of the appropriate standard diluent. Do not use assay buffer to dilute standards.
3. Gently vortex 1–3 sec and incubate on ice for 30 min. Be consistent with the incubation time for optimal assay performance.
Prepare Standard Dilution Series
The cytokine concentrations specified for the 8-point standard dilution set have been selected for optimized curve fitting using the 5-parameter logistic (5PL) or 4-parameter logistic (4PL) r Manager™ software. Results generated using dilution points other than those listed in this manual have not been optimized.
1. Label a set of 1.5 ml Eppendorf tubes as shown in the diagram on the next page.
e the pellet is at the bottom.
egression in Bio-Plex
®
7
2. Pipet the appropriate volume of standard diluent into the tubes (see diagram below). Use serum standard diluent for serum samples, plasma standard diluent for plasma samples, and culture medium for culture samples.
3. Add 25.6 µl of the reconstituted standard to the first 1.5 ml tube containing 374.4 µl of standard diluent. Vortex gently. This is identified as S1 in the diagram below and in the product insert provided with assay.
4. Continue making serial dilutions of the standard as shown. After making each dilution, vortex gently and change the pipet tip after every transfer.
NOTE: Running an additional two 0 pg/ml blanks is strongly recommended. Use 50 µl of the appropriate standard diluent as the blank sample. The 0 pg/ml points should be formatted as blanks, not as points in the curve, when using Bio-Plex Manager software. The blank wells are also useful for troubleshooting and determining LOD.
5. Keep the standards on ice until ready for use. Standards should be used immediately and should not be frozen for future use.
Standard Dilution Series
8
Section 7
Serum Serum standard diluent
Plasma Plasma standard diluent
Culture supernatant Same culture medium used
to prepare samples
Sample Diluent
Control Preparation (Optional)
One tube of lyophilized cytokine control is provided in each Bio-Plex®Precision Pro™ cytokine assay. The preparation of high, medium, and low controls is optional to monitor plate-to-plate variations. This section provides instructions on how to reconstitute the Iyophilized control. The product insert provided with the assay lists the concentration of the reconstituted control. The reconstituted control can then be further diluted to prepare any concentration of user­specified quality controls. To ensure optimal assay performance, the cytokine controls should be prepared in a manner consistent as that used to prepare the cytokine standards.
Reconstitute Cytokine Controls
1. Gently tap the glass vial containing the lyophilized cytokine control on a solid surface to ensur
2. Reconstitute 1 vial of lyophilized control with 500 µl of the appropriate diluent. Do not use assay buffer to dilute controls. This is identified as C0 in the product insert provided with the assay.
e the pellet is at the bottom.
3. Gently vortex 1 – 3 sec and incubate on ice for 30 min. Be consistent with the incubation time to ensure optimal assay performance.
4. The reconstituted cytokine control should be further diluted to create the desired QC samples in the same diluents specified in the table above. To obtain the concentration of each reconstituted cytokine control, refer to C0 in the product insert provided with the assay.
9
Section 8 Assay Instructions
The following instructions apply to Bio-Plex®Precision Pro™ cytokine assays. All of the necessary components are provided premixed for ease of use.
Plan Experiment
1. Assign which wells of a 96-well plate will be used for each standard, contr
ol, and sample (see the example below).
2. Determine the total number of wells that will be used in the assay. Include a 25% excess (or add 2 wells for every 8 wells used) to ensure that enough diluted coupled beads, detection antibodies, and streptavidin-PE are prepared.
Example Plate
10
Prepare Coupled Magnetic Beads
# of Wells 25x Beads (µl) Assay Buffer (µl) Total Volume (µl)
96
48
32
24
240
120
80
60
5,760
2,880
1,920
1,440
6,000
3,000
2,000
1,500
Protect the beads from light by covering the tubes with aluminum foil. Keep all tubes on ice until r
eady to use.
1. Vortex the coupled beads (25x) at medium speed for 15–20 sec.
2. Prepare a sufficient volume of coupled beads (1x) using assay buffer. Each well requires 2 µl of coupled beads (25x) adjusted to a final volume of 50 µl with assay buffer (refer to the example below).
Example Bead Calculations
Calibrate Vacuum Apparatus
The vacuum apparatus must be calibrated at the beginning of the assay to ensur
e an optimal bead yield. For more detailed instructions, refer to
the Bio-Plex suspension array system hardware instruction manual.
1. Prewet all the wells of a 96-well filter plate with 100 µl of assay buffer.
2. Place the filter plate on the vacuum apparatus and turn on the vacuum to the maximum level.
3. Press on the filter plate and note the time required to remove the buffer from the wells by vacuum filtration. The evacuation time should be 2–5 sec.
If the evacuation time is <2 sec, the pressure is too high. Open the vacuum control valve slightly and repeat steps 1–3.
If the evacuation time is >5 sec, the pressure is too low. Close the vacuum control valve slightly and repeat steps 1–3.
11
Assay Procedure
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Gently cover the filter plate with a new sheet of sealing tape. Place the filter plate on a microplate shaker and then cover with aluminum foil. Shake the filter plate at room temperature at 1,100 rpm for 30 sec, then at 300 rpm for the specified incubation time.
Bring all buffers to room temperature. Avoid bubbles when pipetting.
A
ssay Key – The following terms are repeated throughout the assay procedure. Refer to these detailed instructions when wash, incubate, and vacuum-filter are shown in bold.
1. Equilibrate the diluted standards, samples, and controls at room
temperature for 20 min prior to use.
2. Prewet and block the desired number of wells in a 96-well filter plate
with 100 µl of assay buffer and vacuum-filter. If fewer than 96 wells ar
e required, mark the plate to identify the unused wells for later use
and cover the unused wells with sealing tape.
3. Vortex the coupled magnetic beads (1x) for 15–20 sec at medium
speed. Add 50 µl to each well and immediately vacuum-filter.
4. Wash twice.
5. Gently vortex the diluted standards, controls, and samples for 1–3
sec. Add 50 µl of standard, contr the pipet tip after every volume transfer. Incubate for 1 hr.
12
ol, or sample to each well, changing
6. While the samples are incubating, perform a 30 sec quick-spin
# of Wells
10x Detection
Antibody (µl)
Total Volume (µl)
96
48
32
24
300
150
100
75
2,700
1,350
900
675
3,000
1,500
1,000
750
Detection Antibody
Diluent (µl)
centrifugation of the detection antibody (10x) prior to pipetting to collect the entire volume at the bottom of the vial.
7. Prepare a sufficient volume of detection antibodies (1x) using detection antibody diluent. Each well requires 2.5 µl of detection antibodies (10x) adjusted to a final volume of 25 µl with detection antibody diluent (refer to the example below).
Example Detection Antibody Calculations
8. After incubating the samples, slowly remove and discard the sealing tape, then vacuum-filter.
9. Wash 3 times.
10.
Vortex the detection antibodies gently and add 25 µl to each well. Incubate for 30 min.
11.
While the detection antibodies are incubating, perform a 30 sec quick-spin centrifugation of the streptavidin-PE (100x) prior to pipetting to collect the entire volume at the bottom of the vial.
12. Prepare a sufficient volume of streptavidin-PE (1x) using assay buffer. Each well requires 0.5 µl of streptavidin-PE (100x) adjusted to a final volume of 50 µl with assay buffer (refer to the example on the following page).
13
# of Wells
100x
Streptavidin-PE
(µl)
Total Volume (µl)
96
48
32
24
60
30
20
15
5,940
2,970
1,980
1,485
6,000
3,000
2,000
1,500
Assay Buffer (µl)
Example Streptavidin-PE Calculations
13. After the detection antibody incubation, slowly remove and discard
the sealing tape, then vacuum-filter.
14. Wash 3 times.
15.
Vortex the streptavidin-PE (1x) vigorously and add 50 µl to each well. Incubate for 10 min.
16.
After the streptavidin-PE incubation, slowly remove and discard the sealing tape, then vacuum-filter.
17. Wash 3 times.
14
18. Add 125 µ r
esuspend the beads. Acquire the data immediately as described in
l of assay buffer to each well. Incubate for 30 sec to
Section 9.
Section 9 Data Acquisition
Bio-Plex®Precision Pro™ cytokine assays require the use of Bio-Plex Manager™ software version 4.1 or higher. Recommendations for acquiring data using the Bio-Plex suspension array system are listed below. Alternatively, refer to the Bio-Plex Manager™ software user guide or the instructions provided with the Luminex instrument.
Prepare System
1. Empty the waste bottle and fill the sheath fluid bottle before starting (if HTF not pr potential data loss.
2. Turn on the reader and microplate platform (and HTF if present). Allow the system to warm up for 30 min.
3. Select Start up and follow the instructions to prepare the reader to acquire data. If the system is idle for 4 hr, the lasers will automatically turn off and a 30 min warm-up period will again be required prior to acquiring data. Select Warm up and wait for the optics to reach operational temperature.
Calibrate With High RP1 Target Value
Calibrate using Bio-Plex calibration beads and target values. Daily calibration is recommended before acquiring data.
esent). This will prevent fluidic system backup and
1.
Select Calibrate and confirm that the default values for CAL1 and CAL2 are the same as the values on the Bio-Plex calibration bead labels. Use the Bio-Plex High RP1 target value for CAL2 calibration for Bio-Plex Precision Pro cytokine assays.
NOTE: When acquiring data for Bio-Plex Precision Pro cytokine assays with a Luminex instrument, Luminex software, and Luminex calibration beads, it is necessary to convert the Luminex CAL2 calibration bead RP1 target value using the following equation:
Bio-Plex High RP1 target value = (Luminex RP1 target value) x 4.55
15
Add the new target value to the Luminex software by selecting Calibrate, then New under the Reporter Channel in the Start Calibration dialog. Enter the new target value and save it as a new lot. Then calibrate using the new RP1 target value.
2. Select OK and follow the instructions for CAL1 and CAL 2 calibration.
Prepare Protocol
1. Open a new protocol by selecting File, then New from the main menu. Locate the steps at the left of the protocol menu.
NOTE: T
o minimize data entry, preset lot-specific Bio-Plex Precision
Pro cytokine assay protocols are available for download at
www.bio-rad.com/bio-plex
2. Select Step 1 (Describe Protocol) and enter information about the assay
.
3. Select Step 2 (Select Analytes) and choose the panel for Cytokines. Choose the target proteins for the assays on the plate. Note that this information will already be entered with the preset downloaded protocol.
Plate Formatting Example
16
4. Select Step 3 (Format Plate) and click on the Plate Formatting tab. Click on and drag the cursor over all the wells that contain standards. Then click on and drag the cursor over the wells that contain blanks. Repeat with to identify all the wells that contain controls and to identify all the wells that contain samples.
NOTE: If the preset protocol was downloaded, a formatted plate will already be provided. Make any necessary changes to the preset formatted plate to match your plate setup.
5. Select Step 4 (Enter Standards Info) to enter standards information. Note that this information will already be entered with the preset download protocol.
a) Select each analyte individually from the pull-down cell.
b) Select the Enter Automatically option and then select the most
concentrated value as S1.
c) Enter the concentration of S1 from the product insert provided
with the assay.
d) Enter the dilution factor as 4 and select Calculate. The standards
information will be populated for the selected analyte.
e) Deselect the box for same concentration values for all analytes.
Repeat steps 5a through 5d for each analyte in the assay.
6. Select Step 5 (Enter Controls Info) to enter controls information. This is where the concentration of the user-specified controls is entered into the protocol.
a) Select each analyte individually from the pull down cell.
b) Enter the description, concentration, and dilution information for
each user-specified control.
c) Deselect the box for same concentration values for all analytes.
Repeat steps 6a and 6b for each analyte in the assay.
7. Select Step 6 (Enter Sample Info) and enter sample information.
17
Acquire Data
1. Shake the assay plate at 1,100 rpm for 30 sec immediately before acquiring data. Failur time due to bead settling.
2. Check that the filter plate is flat. While pressing on one end of the plate, observe the distance that the opposite end of the plate is raised off a flat surface. If the distance is >1 mm, transfer all contents to a flat-bottom 96-well plate or another filter plate.
3. Visually inspect the plate and ensure that the assay wells are filled with buffer prior to placing the plate in the Bio-Plex microplate platform.
4. Slowly remove the sealing tape and any plate cover before placing the plate in the reader.
5. Select Step 7 (Run Protocol):
a) Specify data acquisition for 100 beads per region.
b)
In Advanced Settings, set the Bead Map to 25 region.
e to do so will result in increased data acquisition
NOTE: Bio-Plex Pr beads and require the use of the 25 region map available in Bio­Plex Manager software version 4.1 or higher.
c) In Advanced Settings, set the sample size to 50 µl.
d)
In Advanced Settings, confirm that the default DD gate values are set to 5000 (low) and 32000 (high).
NOTE: When using a Luminex instrument, set the gates accor
ding to the Luminex procedure located in the manual.
e) Select Start and save the .rbx file. Then follow the instructions for
data acquisition.
18
ecision Pro cytokine assays contain magnetic
6. If acquiring data from more than one plate, empty the waste bottle and refill the sheath bottle after each plate (if HTF not present). Select Wash Between Plates and follow the instructions for fluidics maintenance. Then repeat the Prepare Protocol and Acquire Data steps.
NOTE: Use the W run to reduce the possibility of clogging the instrument.
7. When data acquisition is complete, select Shut Down and follow the instructions.
Reacquire Data
It is possible to acquire data fr Rerun/Recovery mode located below Start in Step 7 (Run Protocol).
1. Check the wells where data will be acquired a second time.
Any previous data will be overwritten.
2. Remove the buffer by vacuum filtration and add 125 µl of assay
buffer to each well. Cover the filter plate with a new sheet of sealing tape.
3. Repeat Acquire Data steps 1–6 to acquire data a second time.
The data acquir however, the data acquisition time will be extended since fewer beads are present in each well.
ash Between Plates command after every plate
om a well or plate a second time using the
ed should be similar to the data acquired initially;
19
Section 10 Troubleshooting Guides
This troubleshooting guide addresses problems that may be encountered with
®
Bio-Plex listed below, review the possible causes and solutions provided. This will assist you in resolving problems directly related to how the assay steps should be performed. Poor assay performance may also be due to the Bio-Plex array reader. To eliminate this possibility, we highly recommend use of the Bio-Plex validation kit. This kit will validate all the key functions of the array reader and assist the user in determining whether or not the array reader is functioning properly.
Possible Causes Possible Solutions
High Inter-Assay CV
Standards were not reconstituted consistently
Precision Pro™ cytokine assays. If you experience any of the problems
Incubate the reconstituted standards for 30 min on ice. Always be consistent with the incubation time and temperature.
Reconstituted standards and diluted samples were not stored properly
High Intra-Assay CV
Bottom of filter plate not dry
20
Reconstituted standards and diluted samples should be prepared on ice as instructed. Prior to plating, the reconstituted standards and diluted samples should be equilibrated to room temperature.
Dry the bottom of the filter plate with absorbent paper towel (preferably lint-free) to prevent cross­contamination.
Possible Causes Possible Solutions
Pipetting technique
Reagents and assay components were not equilibrated to room temperature prior to plating
Contamination with wash buffer during wash steps
Slow pipeting samples and reagents across the plate
Pipet carefully and slowly when adding standards, samples, detection antibodies, and streptavidin-PE, especially when using a multichannel pipet. Use a calibrated pipet. Change pipet tip after every volume transfer.
All reagents and assay components should be equilibrated to room temperature prior to plating.
During the wash steps, be careful not to splash wash buffer from one well to another. Be sure that the wells are filtered completely and that no residual volume remains. Also, be sure that the microplate shaker setting is not too high. Reduce the microplate shaker speed to minimize splashing.
Sample pipeting across the entire plate should take less than 4 min. Reagent pipeting across the entire plate should take less than 1 min.
21
Possible Causes Possible Solutions
Low Bead Count
Miscalculation of bead dilution
Check your calculations and be careful to add the correct volumes.
Beads clumped in multiplex bead stock tube
Vacuum on for too long when aspirating buffer from wells
Did not shake filter plate enough before incubation steps and prior to reading
Reader is clogged
Low Signal or Poor Sensitivity
Standards reconstituted incorrectly
Detection antibody or streptavidin-PE diluted incorrectly
Vortex for 15–20 sec at medium speed before aliquoting beads.
Do not apply vacuum to the filter plate for longer than 10 sec after the buffer is completely drained from each well.
Shake the filter plate at 1,100 rpm for 30 sec before incubation steps and immediately before reading the plate.
Refer to the troubleshooting guide in the Bio-Plex hardware instruction manual.
Follow the cytokine standard instructions carefully.
Check your calculations and be careful to add the correct volumes.
22
Possible Causes Possible Solutions
High Background Signal
Incorrect buffer was used (for example, assay buffer used to dilute standards)
Use sample matrix or serum standard diluent to dilute cytokine standards.
Spiked “0 pg/ml” wells by mistake
Streptavidin-PE incubated too long
Poor Recovery
Expired Bio-Plex reagents were used
Incorrect amounts of components were added
Microplate shaker set to an incorrect speed
Pipetting technique
Be careful when spiking standards. Do not add any antigens in the 0 (blank) point.
Follow the procedure incubation time.
Check that reagents have not expired. Use new or unexpired components.
Check your calculations and be careful to add the correct volumes.
Check the microplate shaker speed and use the recommended setting. Setting the speed too high may cause splashing and contamination. Use the recommended plate shaker.
Pipet carefully and slowly when adding standards, samples, detection antibodies, and streptavidin-PE, especially when using a multichannel pipet. Use a calibrated pipet. Change pipet tip after every volume transfer.
23
Section 11 Safety Considerations
Eye protection and gloves are recommended while using this product. Consult the MSDS for additional information.
Human Source Material. Treat As Potentially Infectious.
The Bio-Plex human origin. This material should be handled as if capable of transmitting infectious agents. Please use universal precautions. The material has been tested by an FDA approved test and found negative for HBsAg, HIV 1/2 Ab, HIV-1 Ag, and HCV. No test method can provide total assurance that hepatitis B virus, hepatitis C virus, human immunodeficiency virus, or other infectious agents are absent. These components should be handled at Biosafety Level 2 containment [US Government publication: Biosafety in Microbiological and Biomedical Laboratories (CDC, 1999)]. Handle Bio-Plex Precision Pro serum and plasma standard diluents as potentially biohazardous material under at least Biosafety Level 2 containment.
®
Precision Pro™ cytokine assays contain components of
24
xMAP is a trademark of Luminex Corp.
Costar is a trademark of Coming Costar Corporation. Eppendorf is a trademark of Eppendorf-Netheler-Hinz GmbH. Luminex 100 and xMAP are trademarks of Luminex Corporation. Multiscreen is a trademark of Millipore Corporation. Vortex-Genie is a trademark of Scientific Industries, Inc.
By purchasing this kit, which contains fluorescent labeled microsphere beads authorized by Luminex, you, the customer, acquire the right under Luminex's patent rights* to use this kit or any portion of this kit, including without limitation the microsphere beads contained herein, only with Luminex’s laser-based fluorescent analytical test instrumentation known under the name of Luminex 100, for example as marketed by Bio-Rad Laboratories, Inc. in the Bio-Plex system.
*Including, but not limited to US patent 5,981,180; 6,046,807; 6,057,107.
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