Support
Frequently Asked Questions 
How does this array work?
The Quansys Multiplexed ELISA Array consists of a non-contact printed array of capture antibodies to a variety of either mouse or human cytokines. The user adds an antigen standard and samples to individual wells of a 96-well plate. After incubation and washing, a mixture of biotinylated antibodies is added to the plate. This is followed by incubating with streptavidin-HRP and is completed by capturing the light produced from adding chemiluminescent substrate with a CCD imaging system. The chemiluminescent signals from individual spots are measured using a CCD camera. Pixel intensity values are used to construct a standard curve individual standard curve and calculate the concentrations of the unknown sample for each system.
Are the results quantitative?
Yes, the array typically uses a five-point standard curve to accurately quantify samples. The five-point curve has been designed to encompass the biological ranges for individual cytokines.
Does the standard curve encompass the lower limit of detection (LLD) for each cytokine?
No, in some cases the typical five-point standard curve does not reach the LLD for a given cytokine. The user has an option of using additional dilutions of the antigen mix to achieve the LLD for a given cytokine.
How should I dilute my sample if I expect a high response for one bio marker and a low response for another?
We recommend testing each sample in step dilutions. For example, when testing cell culture supernatant for unknown cytokine concentrations; a 1:2, a 1:10 , and a 1:50 dilution are typically used.
The standard curves shown in the Certificate of Analysis use pixel intensities on the Y-axis against concentrations on the X-axis. Will different CCD cameras give different pixel intensities and how will this affect my assay? Yes, different CCD cameras give different pixel intensities based on the sensitivity of the camera. However, this will not affect assay performance or standard curve generation as the pixel intensities are relative values.
Do I have to use the entire 96 well plate in one assay?
Once the lyophilized reagents are reconstituted they should be used immediately. If the user desires to run several assays using the 96 well plate, the reconstituted antigen standards should be immediately aliquoted and frozen at -20°C. The entire kit contents should be used within one week of reconstitution. Detailed information on kit storage after reconstitution can be found in the User's manual.
Can I stop the assay once I start it?
No, for best results it is recommended that the assay be completed once started. After reading the results with a CCD camera, the user has the option to delay data analysis to a convenient time.
What additional equipment (not provided in the kit) are required to run this assay?
The user will need to provide a pipette and CCD imager. We also recommend an automatic plate washer for best results.
What CCD imagers can be used to image the Quansys Multiplexed ELISA plate?
The Quansys Multiplexed ELISA Array plate can be read by a number of CCD imaging systems and gel documentation systems such as Alpha Innotech Fluorchem SP, Kodak 4000 MM, Fujifilm LAS-3000, Bio-Rad Versa Doc 4000, and others. A cooled and non-cooled CCD imager with at least 12-bit outputs contained in a light tight box are appropriate for imaging. Our array format and the Quansys Array Software are compatible with most CCD imaging systems. High-resolution cameras in light tight boxes with at least 19" from the lens to the plate if imaging from the top or 6" from the bottom are ideal for this application, but not required.
How is the data gathered from the CCD imager analyzed?
The software allows the user to open the plate image, mark the spots, and analyze the pixel intensity of individual spots on the plate. This software does not automatically find spots or provide detailed data reports (standard curve plots or statistical analysis). Data should be exported into Microsoft® Excel® or a similar program for further analysis and data management.
What kind of samples can be run in the Quansys Multiplexed ELISA Array?
The Quansys Multiplexed ELISA Array has been tested with serum, plasma, whole blood, urine, and cell and tissue lysate. We have experienced no interference from FBS, 1% NP-40, 1% Tween, 1% Triton X-100, heparin (30 mg/ml), 1M urea, 20 mM EDTA, 20% citrate. SDS has been shown to interfere with the assay. Human samples containing human antibodies must be diluted 1:2 in the provided sample dilution buffer. If tissue homogenates or cell lysates are used, centrifuging is recommended to clarify samples prior to using in the assay. When using tissue homogenates, we recommend preparation in a protein-free buffer so that samples can be tested for total protein to normalize cytokine responses.
How much sample is required for the Quansys Multiplexed ELISA Array?
The Quansys Q-Plex™ Array requires 30 µl total volume per well (sample plus diluent). Smaller sample volumes may be used when high levels of bio markerss are anticipated. Mouse samples can be run neatly. However, human samples containing human antibodies MUST be diluted 1:2 in sample dilution buffer prior to running the assay.
How long does it take to complete the Quansys Multiplexed ELISA protocol?
Most protocols require as little as two and a half hours for completion. After imaging the plate, data analysis may be carried out later.
I want to compare samples assayed at various time points, how much variance does the Quansys Multiplexed ELISA array have?
The Quansys Multiplexed ELISA assay has <15% CV between kit lots and has been validated at <25% error when compared to known controls.
I want to measure a protein I don't see displayed or I need to measure a unique set of cytokines that you don't currently offer. Can Quansys build an assay for me?
Yes, Quansys Biosciences specializes in assay development, please call or email for details and pricing.
I don't have access to a CCD camera system. Is there a testing service?
Yes, your samples can be mailed to Quansys where they will be tested using the Quansys Multiplexed ELISA platform. Data, along with statistical analyses will be provided to the user within two weeks. Please call for shipping details and pricing.
