27th June, 2017

An application that we have proven to be successful for aptamers is Enzyme-Linked Oligonucleotide Assays (ELONA). These are similar to ELISA but utilise the benefits that aptamers offer.

ELONA use aptamers in two ways; to capture the target molecule on the plate and for use as a detection molecule. After the sample is immobilised on the plate (96 well) complementary aptamers labelled with reporter molecules, are added. After washing off any excess labelled aptamer, the plate can be read to quantify the target molecule within the sample.

Advantages of ELONA

While the science behind ELONA is very similar to ELISA, there are several benefits to using ELONA for your assays.

1. Increased Sensitivity

By using the principle of counter-selection (see  here), aptamers can be designed to not recognise molecules closely related to the target of interest. This level of sensitivity is not achievable with antibodies where similar proteins are often not distinguishable.

2. Wider range of outputs

Unlike ELISA, where detection is measured using fluorescence, ELONA can use many different reporter systems to obtain a quantifiable output.

3. Easier to develop

During aptamer selection, multiple aptamers are identified which are capable of binding to different epitopes on the target’s surface. This enables aptamer pairs required for ELONA to be determined very easily.

4. Works with existing technology

Utilisation of aptamers can be based on existing technology. An ELONA can be designed to work alongside all existing plate reader models, keeping costs down. Also, ELONA can be designed to complement existing high-quality monoclonal antibodies. This helps optimisation of existing ELISA plates.

The identification and generation of aptamers is much quicker than that of antibodies. The production of novel antibodies for an ELISA can take up to a year. However, discovery and production of an aptamer pair for ELONA can be achieved within 3 months.

If you would like to discuss ELONA or any other application for aptamers please call us on 01904 567 790 or email info@aptamergroup.co.uk.