Hi,

I think you can ask different companies about their product then you can compare the quality of the kit. Because most of the time price depends on quality of the product.

In our case, we are using kit from millipore.

I think so. But you have to check the company browser for the sensitivity of the kit.

There are differences in quality, which do, however, not correlate with price, but with suppliers.

Certainly, there will be a difference in sensitivity. This should be available in the product insert (generally available on-line). Precoated plates are generally more sensitive and more reproducible than assays you coat yourself. Also, if you are looking to minimize optimization, then a complete kit with precoated plates and all buffers included is your best bet, although they are usually more expensive (because they have been optimized). This will also be your safest bet if you don't have a lot of experience with ELISA.

The difference in sensitivity comes from the quality of the capture antibody and the antibody that are used in the kit to develop ELISA. You can use monoclonal antibody that has good affinity to capture and polyclonal to develop. R&D usually has good quality antibody and proteins to use as a standard curve.

They differ in sensitivity, protocols and unfortunatelly quality. We tested many manufacturers (R&D, eBiosciences, BioLegend, Diaclone, IBL, RayBioTech, USCN Life Sciences etc). , If you list the molecules, which zou are planning to measue, maybe I can advice something. I also agree that R&D keep the good lvl.

The antibody pair is the most important in my opinion. Wash buffer, blocking, stopping solution can be easily prepared in the lab. By the way, many companies use the same antibodies (check for clone numbers). If you have a lot of samples than pre-coated plates might not be enough since they come in packages of 1 or 2. Also, if you get enough antibodies for 10 or more plates than you don't have to worry about differences between lots and batches.

Make sure to check for the sensitivity and the range of measurements. Some ELISA needs special stat program to construct the standard curve. Expensive kits take shorter time but less expensive ones work good too.

Price does not always depend or correlates directly with quality. There are supplieres selling low quality ELISA for 400 Euro each. On the other hand you can have very specific and highly sensitive ELISA for nearly the same price by other supplier.

Thank you for your answers! I will start with a "semi"expensive kit (RnD) and make my own washing buffer and stop solution. We'll see how it goes - possibly I will need to go for the precoated plates in the end after all.

High sensitive R&D systems kits are useful to detect samples from cell culture supernatant

I suggest one of my publications to you: Zheng, T.; Cherubin, P.; Cilenti, L.; Teter, K.; Huo, Q. A simple and fast method to study the hydrodynamic size difference of protein disulfide isomerase in oxidized and reduced form using gold nanoparticles and dynamic light scattering. Analyst 2016, 141, 934.

You will understand from here why ELISA varies from one product to another. More expensive plate does not mean higher quality!

I also suggest you to try a new immunoassay technology-you can easily develop and use this assay using a single antibody that you have and the assay result is obtained in 5-30 min:

www.nanodiscoveryinc.com