BIOSENSORS: PRINCIPLES, TYPES, NANOBIOSENSOR TECHNOLOGIES, AND BIOMEDICAL APPLICATIONS—A COMPREHENSIVE REVIEW

Abstract

Biosensors are analytical devices that combine a biological recognition element with a physicochemical transducer to detect and quantify specific analytes. Their selectivity, sensitivity, rapid response, portability, and potential for low-cost operation have made them important tools in biomedical analysis, environmental monitoring, food analysis, and pharmaceutical applications. This review summarizes the fundamental principles of biosensing, major recognition and transduction components, important performance characteristics, and the development requirements of practical biosensors. It further discusses electrochemical and optical biosensors, with emphasis on nanobiosensors and their role in improving analytical sensitivity through nanomaterials. Applications in glucose monitoring, metabolic assessment, environmental detection, and biomedical diagnostics are also reviewed. The article highlights the continuing development of miniaturized, portable, and sensitive biosensing systems for clinical and other analytical applications.