A capture sandwich immunoassay is used to detect an antigen (target) with the use of a capture antibody attached to the surface of a microsphere and a detection antibody that incorporates a fluorescent label, forming a “sandwich.” This assay is commonly used to measure a large number of hormones, blood products, enzymes, drugs, disease markers, and other biological molecules.
A competitive immunoassay enables detection of an antigen (target) with use of a single capture antibody attached to the surface of a microsphere and a competitive, labeled antigen reversibly bound to the antibody. An analyte of interest in the sample competes with the labeled antigen causing a decrease in detected signal. A reverse version of the assay is also possible in which the analyte in the sample competes away the labeled antibody in solution rather than on the surface of the microsphere. A version of competitive assays on xMAP Technology was used extensively in the development of the Gardasil® vaccine.
A serology assay enables the detection of an antibody (target) with the use of a capture protein antigen attached to the surface of a microsphere. A detection antibody that incorporates a fluorescent label is used to quantify the amount of target antibody present. This assay is useful when serum antibodies need to be measured, such as for the response to a vaccine, allergic reactions, or autoantibody detection.
Microarray technology allows for ultra high density gene expression profiling, but cost, throughput, and reproducibility with a two dimensional array are problematic in drug trials and in the clinic, where only a moderate number of genes are screened in thousands of samples. More samples can be screened faster using qPCR methods, but cost and the number of genes measured can be limiting.
The solution-phase kinetics of xMAP® Technology offers the best of both worlds for gene expression—moderate to high multiplexing (beyond 100-plex) and high-throughput with robust reproducibility.
xMAP Technology is ideal for all sorts of genotyping applications—including identity testing, pharmacogenomics, infectious disease screening, population genetics, genetic screening, or DNA sample profiling. Using xMAP Technology, the laboratory can multiplex both the amplification and detection steps, enabling the screening of up to 500 samples per day for genetic markers—boosting productivity with higher throughput, and cutting costs by requiring smaller amounts of sample DNA.
MicroRNAs are small non-coding sequences of RNA that are important in transcriptional regulation and post-transcriptional regulation of gene expression. Assays built using Luminex’s technologies to study miRNA can be run as multiplexes of your choosing and save you time and money compared to other methods, such as PCR. The flexibility of xMAP® Technology allows you to choose just the miRNAs that are relevant to your research. Detection of targets of interest can be quantified in less than five hours. Explore the QuantiGene Singleplex miRNA probes available from Affymetrix or click here for details on building your own microRNA assay.
GARDASIL® is a registered trademark of Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Whitehouse Station, NJ, U.S.A.