Meso Scale Discovery (MSD) electrochemiluminescence technology is an excellent platform for measuring analytes in complex biological samples. MSD offers enhanced sensitivity, a broader dynamic range, simple protocols, and multiplexing capacities. Therefore, MSD assays have become a crucial component of the drug development and discovery process. But what is the drug development process? The primary aim of the drug development process is to screen and identify potential molecules that can treat disease and medical disorders.
MSD combines electrochemiluminescence and Multi-array technology to provide rapid and highly dense information through miniaturization and parallel processing of study samples. The basic workflow of MSD assays is similar to traditional ELISA, except they employ meso scale discovery electrochemiluminescence
detection compared to the colorimetric reaction in ELISA assays. MSD assays have several advantages over conventional ELISAs. Hence, they are preferred by research organizations, pharmaceutical companies, and government institutions. However, there are some essential considerations for MSD assays. The current article highlights five core considerations for MSD assays.
Assay format
Although researchers can use direct binding assays or competitive formats in Meso Scale Discovery assays, the sandwich format is the most common type of MSD format. MSD has three primary sandwich assay formats employing different antibody coating strategies. These strategies include:
- Direct conjugation of MSD Sulfo-Tag to the detection antibody
- Binding of Sulfo-Tag streptavidin complex to the biotinylated detection antibody
- And binding of detection antibody to Sulfo-Tag conjugated anti-species antibody.
Nevertheless, MSD can also be performed without antibodies as capture reagents. Other capture materials include proteins, antigens, carbohydrates, peptides, lysates, membranes, cells, and virus-like structures.
Plate surface for MesoScale Multiplex assays
A combination of surface type and electrode size decides the quantity of capture reagent researchers can coat on an MSD plate. MSD plates have two different surfaces, hydrophobic and hydrophilic. Standard MSD plates have hydrophilic surfaces, while high bind plates have hydrophobic surfaces.
Depending on assay goals, researchers can choose from hydrophilic or hydrophobic surfaces. Standard plates offer enhanced sensitivity while high bind hydrophobic plates aid researchers measure analytes present at higher concentrations. With complex samples, standard plates may display reduced non-specific binding. However, researchers must test both plate surfaces to choose an optimum alternative.
Plate coating of Meso Scale Discovery Multiplex assays
Researchers can use solution coat or spot coat MSD assays. Solution coating is similar to ELISA assays, whereas spot coating only coats the electrode. Though both methods are feasible, spot coating generally provides enhanced sensitivity. However, researchers must test both coating strategies during method development.
Prototype printing service
Researchers can coat their assays or avail of MSD’s prototype printing service. Prototype Printing Service is an excellent, affordable option to coat MSD’s multi-array plates with materials of choice. Customers can choose the plate type, coating concentration, and coating buffer. Furthermore, MSD offers coating optimization packages, where they coat different plate surfaces to identify the optimal coating strategy for customers.
Assay variability and signal reproducibility
Inter and intra assay signal reproducibility are crucial for reliable and accurate results. Several factors can influence signal reproducibility. These factors include pipetting variability, read buffer concentration, shaking speed, reagent storage, plate washing equipment, and dissociation rates.