biosenzori

Biosensors are analytical devices that couple a biological recognition element with a transducer to convert a biological interaction into a measurable signal. The biological component is chosen for its specific interaction with a target analyte and may include enzymes, antibodies, nucleic acids, cells, or other biomolecules. The transducer converts the recognition event into a quantifiable electrical, optical, or thermal signal.

Typical biosensor architecture includes a recognition element, a transducer, and an electronic system for signal processing and readout. Performance is described by sensitivity, selectivity, limit of detection, response time, stability, and reproducibility. Transduction methods are diverse and include electrochemical, optical, piezoelectric, and thermal approaches.

The development of biosensors began in earnest in the 1960s with enzyme-based glucose sensors, notably Clark and Lyons' 1962 device. Since then, advances in materials, nanotechnology, and biorecognition have expanded capabilities and reduced size, enabling portable, affordable devices for point-of-care use.

Common biosensor types include enzyme-based sensors for metabolic targets, immunosensors that use antibodies to detect antigens, DNA or aptamer sensors for nucleic acids and toxins, and whole-cell or microorganism-based sensors for environmental monitoring and toxicity assessment.

Applications encompass medical diagnostics and management (such as glucose meters and infectious disease testing), environmental monitoring (pollutants and toxins), food safety (contaminants and pathogens), agriculture, and biodefense. Many modern devices integrate microfluidics, nanomaterials, and smartphone or cloud-based readouts.

Challenges include achieving high selectivity in complex samples, maintaining stability and shelf life, preventing biofouling, ensuring reproducibility and calibration, and meeting regulatory requirements. Ongoing research aims to improve sensitivity, reduce cost, and enable multiplexed, continuous monitoring.