ELISA Wash Buffers
ELISA wash buffers were developed as a high performing washing solution to be used in a variety of versatile ELISA formats. Surmodics™ IVD’s BioFX™ Tris Buffered Saline (TBS) Wash Solution‐10X Concentrate contains non‐ionic surfactant, which does not interfere with assay reactants and reduces non‐specific binding.
The ELISA wash buffer available from Surmodics IVD may be used with antibody-sandwich ELISA’s and Direct ELISA applications
ELISA wash buffers are often used in a variety of ELISA applications. ELISA wash buffers are commonly used to rinse microtiter plates during the coating process and between reagent addition steps during an ELISA assay.
ELISA wash buffers help eliminate any excess material found from the wells of a microtiter plate. This is done without disrupting the intended antigen – antibody binding reaction. With the proper buffering environment, unbound assay components can be washed away without suppressing antibody binding interactions. As a result, non-specific binding is reduced.
Preparation & Protocol
- To produce a 1X working solution, dilute 1 mL of TBS Wash Solution‐10X Concentrate in 9 mL of reagent quality water.
- Allow working solution to equilibrate to room temperature (25°C) prior to use.
- To use the 1X working solution, cover and treat the target surface. Discard solution and repeat the wash step as necessary to optimize the effectiveness of the assay system.
- Length of wash time, number of washes and dilution of wash concentrate may be varied depending on the assay.
The remaining surface area must be blocked to eliminate antibodies or unwanted proteins from absorbing the plate, since the binding capacity of microplate wells is usually higher compared to the amount of protein coated in each well. Wash buffers can prevent unwanted proteins or compounds from absorbing to any remaining unbound plate surfaces.
Finding the right blocker is critical to achieving high signal-to-noise ratios in an immunoassay. Surmodics IVD has a wide selection of reliable, ready-to-use ELISA blocking reagents for assay manufacturing companies and laboratory professionals looking to build sensitive, reproducible immunoassays. We offer several blocking reagents for immunoassays, including point-of-care applications, ELISA’s and more. Each of Surmodics IVD’s ELISA blocking reagents offer assay developers the gold standard in product performance and quality.
Our ELISA blocking reagents include a line of dried protein stabilizers and blockers, sample or assay diluents and western blot blocking buffers. Our ELISA blocking reagents are designed to increase the sensitivity and stability of immunoassays, including ELISA applications while blocking interferences that impact the accuracy and reliability of immunoassays. Furthermore, our ELISA blocking reagents help to reduce cross-reactivity and interferences from Human Anti-Mouse Antibodies (HAMA) and Rheumatoid Factor (RF) as well as non-specific binding.
There are factors that can influence non-specific binding such as various protein interactions unique to samples and antibodies involved. Consider the signal-to-noise ratio when selecting a buffer, as this ratio can be measured as a signal obtained with an endogenous sample or spiked sample diluent divided by the blank (sample diluent that does not contain the target analyte). Excessive blockers and buffers can potentially mask antibody interactions, causing a reduction in signal-to-noise ratio. Empirical testing is required for true buffering optimization of an assay.
It is essential to perform thorough washing in addition to blocking throughout the ELISA process. These steps are necessary, as they remove non-bound reagents and increase the signal-to-noise ratio. Insufficient wash buffers will cause high background, and excessive washing might result in decreased sensitivity caused by the elution of the intended target from the well. Including a blocking agent and using adequate wash buffers can help minimize any background in an assay.