Hi everyone, this opportunity I would like to introduce a relatively novel concept to discuss with you during this blog. That is closely related with the idea of the FoodSmartphone project and we have probably heard about it. What is a biosensor? An intuitive definition could describe it as sort of device capable to measure biological compounds or processes. This first approach is not bad, but we can go deeper into the definition, of what a biosensor is? how it works? And why they are important in daily life?
The first description about a biosensor was given by Leyland C. Clark, in his explanation of an “enzyme electrode” in 1962. Nowadays, the definition involves a wide range of biological recognition elements and transducing systems that are in constant development.
If we go through literature we can find that biosensors are defined as, integrated receptor-transducer analytical devices incorporating a biological sensing element, capable to provide selective information from a sample in a quantitative or semi-quantitative way . This systems are characterized for a biological recognition element such as biological material, biologically derivated materials or biomimics, coupled to a physicochemical transducer or a transducing microsystem which may be optical, thermometric, electrochemical, magnetic or piezoelectric .
They are classified depending on the recognition event in Catalitic Sensors, when they monitor a catalitic event yielding a change in the chemical nature of the species surrounding the sensing surface. Nevertheless, Affinity sensors are those based on ligand binding interaction between the target molecule and the bioreceptor, without analyte conversion.
A typical biosensor contains two basic functional units: a ‘bioreceptor’ (for example, enzyme, antibody or DNA) responsible for selective recognition of the target analyte and a physico-chemical transducer (for example, electrochemical, optical or mechanical) that translates this biorecognition event into a useful signal.
As is mentioned above, a typical biosensor consists in two basic modules. On Image 1, the different components involved in the sensing process are shown. On one hand, “the bioreceptor” (antibody, protein or DNA) that is in contact with the sample and is responsible for the selective recognition event. While on the other hand, the acquired impulse is conducted through the transducer, where is translated in a useful signal that will give the user the information regarding the sample.
Keeping all this information in mind, we can a have better understood about how this devices work. And in my following blogs i will try explain in detail the different components (as the biorecognition elements and transducers available).
To sum up, I think that is important to highlight why biosensors are necessaries? Or when we will use them?
The truth is that we live surrounded by sensors without being aware, for example, a car has thousands of them or even our Smartphones. In order to control the good performance of all the components. Some examples were biosensor technology is used; include healthcare monitoring, clinical analysis and diagnosis, veterinary and agricultural applications. They are also used in environmental pollution control, industrial processing and monitoring. Recent developments have focused on electrochemical and optical biosensors, together with advances in the noninvasive monitoring of biomarkers including metabolites, bacteria and hormones.
Plenty of different approaches have been demonstrated in wearable biosensor devices. Even though, this technology face important challenges associated to stability, validation and accuracy. Solve these technological gaps, becomes essential to develop reliable products in order to grow around this competitive market. In the near future, we can imagine using biosensors as accessories.
Have a nice weekend,