What is Dried Blood Spot Testing? - Chromatography Explores

Making health tests simpler to access is an important strand of health studies. As long as the tests are robust and accurate, any means of making health screening tests cheaper and easier for any given population to access has to be seen in a positive light. The effects are seen not just in developing countries, but in the developed world too.

One such analytical technique is the dried blood spot test - a simple method that can be used for any number of conditions. In the UK, the majority of new born babies are subjected to a dried blood spot test within a few hours of their birth. But the test can be used for much more as discussed in a recent review article published in the journal Biomedical Chromatography - Review of DBS methods as a quantitative tool for anticancer drugs. Let’s take a quick look at the test and see how chromatography is helping to develop the method further.

A flexible method of testing

The dried blood spot test is a simple test used for diagnosing many different conditions from sickle cell anaemia, HIV and now cancer. It is a simple and quick test to perform which means it is convenient to use for screening purposes where many samples have to be taken. Another advantage is that it does not need a doctor or highly trained healthcare professional to administer the test and analyse the results - meaning that the test can be employed in developing areas of the world where access to expensive and sophisticated processes is not always possible.

Simple mechanics of dried blood spot test

Dried blood spot testing uses dried blood spots on a piece of filter paper. The sample is taken by pricking the patient’s finger - or heel in the case of infants - and collecting the blood on the sample paper or card. Usually the sample is allowed to dry before it is treated with an analyte that reacts with the dried sample to produce a reaction. The result of the reaction is usually a simple colour change that can be compared to a reference card giving the tester a simple and quick answer.

Chromatography is used when developing or validating a new test method. Sometimes, the dried blood spot test looks for the reaction of proteins in the sample. The chromatography of samples containing proteins is discussed in the article, Mobile Affinity Sorbent Chromatography Of Proteins. In the article referenced above, chromatography was used to separate the dried blood samples to allow researchers to analyse the contents. Chromatography is one of the most powerful analytical techniques in a chemist’s toolbox.