Aptamer-based and DNAzyme-based biosensors for environmental monitoring

Aptamers and DNAzymes are small single-stranded nucleic acids that fold into a well-defined three-dimensional structure with high specificity to various ligands, such as low-molecular-weight organic or inorganic substrates or macromolecules. Their specificity is comparable with and in certain cases even higher than those of antibodies, and they can be applied for specific detection of various analytes, ranging from small ions to large molecules. This review describes the state of the art in the use of aptamers and DNAzymes in the development of biosensors for environmental monitoring.