Recent advances in DNA aptamer-based fluorescence biosensors from design strategies to diverse applications and future challenges: A review.

Aptamers are single-stranded DNA or RNA oligonucleotides that can bind to specific target molecules with high affinity and specificity. Fluorescence DNA aptamer-based biosensors (aptasensors) have emerged as powerful analytical tools for detecting diverse targets, ranging from food contaminants to disease biomarkers, owing to their exceptional specificity, high sensitivity, and cost-effectiveness. This review systematically summarizes recent advances in the design strategies of fluorescence aptasensors, focusing on three key approaches: (1) fluorescence resonance energy transfer-based signal amplification, (2) nanomaterial-enhanced probes, and (3) multi-channel platforms for simultaneous detection. These design strategies have offered effective detection methods for use in diverse domains including food quality monitoring, medical diagnostics, and environmental analysis. The review highlights emerging portable detection platforms that integrate microfluidic technologies with smartphone-based optical readout systems, demonstrating their potential for field-deployable monitoring. Despite significant progress, challenges such as photobleaching of organic dyes, signal stability in complex matrices, and sensitivity limitations remain to be addressed. Through addressing current technical barriers, next-generation fluorescence aptasensors are positioned to transform three critical domains: (1) miniaturized optics for portability, (2) advanced signal amplification against matrix effects, and (3) intuitive interfaces for field use. These advancements promise to bridge the gap between laboratory analysis and real-world applications.