DNA-based
DNA-based biosensors are devices that utilize the unique properties of DNA molecules to detect and quantify specific analytes or target sequences. These biosensors use DNA as the recognition element, which allows for highly specific and selective detection.
There are different types of DNA-based biosensors, including hybridization-based sensors, aptamer-based sensors, and DNAzyme-based sensors.
Hybridization-based sensors utilize the complementary base-pairing properties of DNA to detect and quantify target sequences. These biosensors typically consist of a single-stranded DNA probe that is complementary to the target sequence. When the target sequence is present, it binds to the probe, resulting in the formation of a double-stranded DNA structure. This binding event can be detected using various techniques, such as fluorescence, electrochemistry, or surface plasmon resonance.
Aptamer-based sensors use short, single-stranded DNA or RNA sequences called aptamers, which are designed to bind specifically to a target molecule or analyte. Aptamers are selected through a process called systematic evolution of ligands by exponential enrichment (SELEX). Once the target analyte binds to the aptamer, it triggers a conformational change that can be detected using different methods, such as fluorescence or electrochemical techniques.
DNAzyme-based sensors utilize catalytic DNA molecules, also known as DNAzymes or catalytic DNA, which can catalyze specific reactions in the presence of a target analyte. These biosensors typically consist of a DNAzyme sequence that is modified to recognize a specific analyte. When the analyte is present, it binds to the DNAzyme, activating its catalytic activity. The catalytic reaction can be detected through various readout methods, such as colorimetry or fluorescence.
DNA-based biosensors have a wide range of applications, including medical diagnostics, environmental monitoring, food safety, and forensic analysis. They offer advantages such as high sensitivity, specificity, and the potential for multiplexed detection. These biosensors are continuously being developed and optimized for various analytes, making them valuable tools in research and practical applications.
