For more than 20 years, we have offered the benefits of MILLIPLEX® multiplex immunoassays, containing all the components you need to detect multiple analytes simultaneously. We provide the largest selection of multiplex immunoassays, analytes, and species to meet the needs of investigators across multiple research areas. Rely on the quality we build into each MILLIPLEX® multiplex kit to produce results you trust.


Quality at Every Step

R&D scientist. With over four decades of immunoassay development and manufacturing expertise, MILLIPLEX® kits are developed and quality tested for accurate, reproducible, and biologically relevant analyte measurements.

Expert Research and Development

With over four decades of immunoassay development and manufacturing expertise, MILLIPLEX® kits are developed and quality tested for accurate, reproducible, and biologically relevant analyte measurements.

Scientific support team. Committed care when and where you need it, with knowledgeable in-house and field-based scientific support for assays and instruments.

Dedicated Support

Committed care when and where you need it, with knowledgeable in-house and field-based scientific support for assays and instruments.

Manufacturing/quality control (QC) scientist. MILLIPLEX® multiplex kits are manufactured in facilities that are ISO 9001:2015 compliant.

Skilled Manufacturing and Quality Control

MILLIPLEX® multiplex kits are manufactured in facilities that are ISO 9001:2015 compliant.

MILLIPLEX® multiplex kit. MILLIPLEX® kit components are produced with quality raw materials and are pre-optimized for easy use and minimal preparation steps.

Optimized Kit Components and Reagents

MILLIPLEX® kit components are produced with quality raw materials and are pre-optimized for easy use and minimal preparation steps.


Lot-to-Lot Reproducibility

Reproducibility across multiple component lots is important to ensure reliable results over time.

Standard Curves are Checked for Each Analyte Across Kit Lots

Each new lot of MILLIPLEX® standards and quality controls (QCs) are compared to the previous lot and a reference lot, our internal gold standard, to ensure lot-to-lot reproducibility and consistency (Figure 1).

Lot-to-lot comparison of standard curves from MILLIPLEX® multiplex kits. Gold Standard lot compared to three subsequent lots (1K-3K) of the analyte Human IL-6 for Cat. No. HSTCMAG-28SK.

Figure 1. Gold Standard lot compared to three subsequent lots (1K-3K) of the analyte Human IL-6 for Cat. No. HSTCMAG-28SK.

Additionally, each lot is tested after lyophilization to confirm that there has been no loss due to the lyophilization process. Full standard curve characteristics and relative potency of analytes are maintained within the specifications of the reference lot (Figure 2).

Graph showing relative potency of an analyte standard is maintained from lot to lot within specifications. Trend chart shows consistent MFI values for a single IL-5 standard curve point across 29 lots of a MILLIPLEX® panel (Cat. No. HCYTOMAG-60K); + 10% of reference lot.

Figure 2. Relative potency of an analyte standard is maintained from lot to lot within specifications. Trend chart shows consistent MFI values for a single IL-5 standard curve point across 29 lots of a MILLIPLEX® panel (Cat. No. HCYTOMAG-60K); ± 10% of reference lot.

Since MILLIPLEX® panels stand the test of time, new standard lots are periodically assigned to be the fresh reference lot against which subsequent lots are compared. All data is compiled in a single database and trend charts are maintained. Other suppliers compare new standard lots to previous lots, without a reference lot, which makes it difficult to compare data from multiple lots since standard curve point values may vary with each new lot and assay drift may occur.

The Importance of Standard Curve Potency

Analyte standard curves from all lots should overlap as closely as possible. Maintaining standard curve potency acceptance criteria is important because it helps to avoid common problems which negatively impact the calculation of analyte concentration in samples (Figure 3). Problematic standard and component lots are never released for sale.

Graph showing an example of problems that may arise when producing new standard lots, such as curve hooking/prozone effect, curve shift, limited linear range, and curves intersecting, highlighting the importance of standard curve potency.

Figure 3. Example of problems that may arise when producing new standard lots, highlighting the importance of standard curve potency.

Quality Controls to Verify Assay Performance

We include two QCs and QC range sheets to qualify and verify assay performance. Assay results for these QCs are to be checked against the provided QC range sheet values to ensure proper pipetting and assay setup have been accomplished. QC values are based on a minimum of six assays run by at least three different operators. The use of high and low QC values serves as an additional checkpoint in case there was user error associated with hydrating or diluting standards.

Additionally, QCs are important for:

  • Translational studies that require more validation, ensuring that the data are reproducible across kit lots
  • Comparing data across multiple sites
  • Comparing assay results from multiple technicians

As with other MILLIPLEX® components, trend charts are maintained for QC ranges across multiple lots. As an added measure, it is recommended that customers include experiment-relevant sample QCs in each assay (Figure 4).

: 96-well plate layout shows the placement of standards, QCs, and the recommended experiment-relevant sample QCs.

Figure 4. 96-well plate layout shows the placement of standards, QCs, and the recommended experiment-relevant sample QCs.

Other MILLIPLEX® Components

Other components that help enhance the quality of MILLIPLEX® kits include:

Serum Matrix

Because blood is a complex matrix that contains proteins that may interfere with the accurate measurement of the desired analyte, using an optimized serum matrix in the standard curve when measuring analytes secreted in serum or plasma:

  • Significantly improves the accuracy of measurement
  • More accurately simulates the conditions of the native analyte present in serum or plasma
  • Mimics the environment of native analytes in serum or plasma

Bead Diluent

A percentage of the healthy population samples contain heterophilic antibodies that can non-specifically bind to the capture and detection antibodies simultaneously, generating a false positive signal. MILLIPLEX® bead diluents contain a cocktail of proprietary reagents that significantly reduce this false signal without reducing the analyte measurement.

Detection Antibody Cocktail

MILLIPLEX® detection antibody cocktails are designed to yield consistent analyte profiles within the panel, lot-to-lot, regardless of plex size (Figure 5).

Graph showing consistent analyte profiles are seen when comparing multiplex and singleplex assays from the same MILLIPLEX® panel, human G-CSF shown.

Figure 5. Consistent analyte profiles are seen when comparing multiplex and singleplex assays from the same MILLIPLEX® panel, human G-CSF shown.


MILLIPLEX® Assay Development

From academia to contract research to big pharma, we meet the ever-increasing demand for high-quality assays to achieve reproducible results.

We consider all the factors that go into assay development, including:

  • Detection and Sensitivity
  • Performance in a Sample Matrix
  • Specificity
  • Selectivity
  • Precision and Accuracy
  • Linearity
  • Stability
  • Cross-Talk
  • Lot-to-Lot Reproducibility
  • Vendor Support

We set and define our MILLIPLEX® assay specifications during kit development. Verification data is provided in each kit protocol. Every MILLIPLEX® kit includes all the optimized reagents and instructions needed to run the assay and read the assay plate on your Luminex® instrument.

In addition to assay specifications listed in the MILLIPLEX® protocols, we evaluate additional performance criteria during our kit development and assay verification process, including dilutional linearity, kit stability, and sample behavior (e.g., sample detectability and stability) described in Table 1.

Table 1.MILLIPLEX® assay specifications can be found in the kit protocol or insert or by contacting Technical Support.