Multiplex Immunoassays

Antibody Arrays

Providing broad, cost-effective early-stage screening, antibody arrays offer a quick and inexpensive analysis of many analytes simultaneously—in less time than it takes to perform a Western blot.   

Similar to an ELISA but with expanded multiplexing capabilities, these semiqualitative antibody arrays can analyze hundreds of different proteins simultaneously with substantially less time and effort.  Rather than a plate, antibody arrays use a membrane as a substrate. Capture antibodies are pre-spotted in duplicate with high-quality capture antibodies for multiplexing.  

With superior specificity, low background noise, and no cross-reactivity, you can count on this assay for clear and consistent data. 

• Fast, economical analysis
• No specialized equipment needed
• Measure more than 100 analytes at once
• Quickly analyze complex signaling responses.

Luminex Multiplex Assays

Luminex multiplex assays are designed to maximize multiplexing capacity and flexibility while maintaining assay specificity. The bead-based Luminex format allows you to better tailor assay selection to your individual research needs while overcoming many common multiplexing challenges. 

Utilizing the same sandwich principles of traditional ELISAs, color-coded microspheres, or beads, are internally dyed with different proportions of red and infrared fluorophores that correspond to a distinct spectral signature, or bead region. Antibodies specific to the desired analyte are coupled to a unique bead region and are incubated with the sample.

Luminex multiplex assays allow you to quantify up to 50 biomarkers with less sample volume than a traditional plate-based ELISA.

• Accurate bead-based assays
• Multiplex up to 50 analytes simultaneously 
• Customize panels to fit your needs
• Rigorously validated for accuracy, reproducibility, and lot-to-lot consistency

Cartridge-Based Immunoassays

With multi-analyte cartridge-based assays, you get the same specificity of a single-analyte ELISA but with greater sensitivity and a broader dynamic range. The automated immunoassay cartridges deliver results in just 90 minutes with better sensitivity and reproducibility than plate-based assays.  

Each cartridge accommodates up to 16, 32, or 72 samples, and each well is sampled three times to give you all the results in triplicate. The antibodies as well as the fluorescent detector are pre-functionalized in the cartridge, eliminating the need to run a standard curve.

Disposable cartridge kits come in a variety of multi-analyte and single-analyte configurations and include everything you need to run your automated ELISA. The reduction in manual steps enables a high level of reproducibility and data quality—all with a method that's fast and easy to transfer. 

• Highly sensitive results in only 90 minutes
• Choose from over 150 validated targets
• Hands-free automation with high-throughput
• Available in single and multi-analyte cartridge formats

Growing demand for immunoassays and surging testing volumes has put pressure on scientists to rein in costs and optimize sample usage by designing multiplex assays to cover several analytes simultaneously. Factor in the time saved by running the equivalent of 20 or more different assays in a single immunoassay workflow, and the benefits of multiplexing are clear.

The ability to measure multiple targets in a single assay allows researchers to detect hundreds of analytes in a single run while being judicious with precious sample volumes. From screening biomarkers for further evaluation to validating results for drug development, multiplex assays provide several important benefits, helping to:

• Conserve limited sample volume
• Lower your cost per data point
• Improve accuracy due to less sample handling
• Optimize productivity
• Save time and resources

Confidence in immunoassay data depends on the accuracy and precision that is only possible from using high-quality antibody reagents. This means selecting antibodies with not only high analyte affinity but also specificity, which is the ability to distinguish between the analyte and other structurally similar components.

While multiplexing offers numerous efficiency advantages, it also introduces several technical challenges that make assay design more complicated. One of the biggest challenges is controlling for cross-reactivity and interference between all the antibodies and proteins in the assay.  Do you get the same results from IL-6 when run alone and when with 20 other analytes? 

Single-analyte assays are designed to be analyte-specific—meaning that every component, from buffer to antibody pairs and more, are custom-tailored for that specific analyte. Assays incorporating multiple analytes do not have this luxury.

Multiplexing requires carefully integrated balances that allow analytes to work consistently together to produce consistent, accurate results. Interfering factors, no matter the mechanism, can result in either reduced or elevated signals relative to the actual concentration of target analyte.  

While validation protocols help ensure that antibodies are producing appropriate results, if the assay isn’t carefully developed and properly designed, achieving optimal performance will be difficult.

At Bio-Techne, we take great care to select the antibodies and proteins that can be plexed harmoniously to reduce interference and maximize performance across all analytes. Meanwhile, our rigorous quality control and validation efforts confirm the performance meets required standards and specifications lot after lot.

While developing a multiplex assay presents several complexities compared to single analyte, plate-based ELISAs, the ability to generate high-quality data while dramatically reducing time and costs needed for testing provides researchers with a powerful advantage. From narrowing down drug candidates in preclinical studies to evaluating therapeutic responses during a clinical trial, multiplex assays provide several important benefits, including the ability to:

• Maximize limited test samples: collect data from just 25μl or less of undiluted sample.
• Minimize experimental variability: derive multiple data points from a single manipulation.
• Optimize productivity: reduce sample preparation and processing time. 
• Improve efficiency: examine multiple analytes in a single sample.

Meeting immunoassay performance goals is an ongoing challenge across research fields. The good news is that today’s scientists have access to an abundance of external experts who have deep technical experience and access to vast libraries of antibodies to help develop their assays. Engaging with an experienced supplier like Bio-Techne and paying attention to the technical factors outlined here will significantly improve your chances of developing high-quality, highly effective multiplex assays.