Overcoming challenges and enhancing Precision: Advancements in optical Bio(sensors) and wearable devices for essential amino acid detection integrated with nanotechnology.

[Display omitted] • A critical review of the advancements in optical bio (sensors) for the detection of essential amino acids. • Sensing mechanisms fundamental to colorimetric detection are discussed. • Synergy between nanotechnology and sensing through signal transduction and amplification has been presented. • The potential and challenges of optical sensors are reviewed.. The rapid advancements in optical sensor research over the past decade have yielded significant progress, owing to their numerous advantages over conventional methods. These advantages primarily stem from their operational simplicity and cost-effectiveness. Particularly, optical sensors offer a colorimetric response that can be easily determined by the naked eye or ultraviolet spectrometer, exhibiting exceptional selectivity. Nanoparticles have found diverse applications across various fields, greatly enhancing numerous aspects of our lives. A predominantly promising opportunity lies in their prospective applications for the detection of essential amino acids, due to their distinctive optical properties. Essential amino acids have an important part in numerous bodily functions and serve as diagnostic indicators for several diseases, given their imbalanced levels within the human body. Therefore, it is crucial to develop a simple approach for the identification and quantification of essential amino acids. However, several challenges still inhibit the full potential of these systems for on-site essential amino acid monitoring. These challenges include ensuring color homogeneity, analyzing real samples, and managing data effectively. Consequently, this comprehensive review explores the progress and challenges associated with the application of nanoparticle-based colorimetric techniques for the detection of essential amino acids under optimized conditions. Furthermore, we explore the fundamental mechanisms for the development of these analytical techniques. Finally, we aim to discuss future directions and opportunities in colorimetric techniques, highlighting their potential as a crucial component of advanced analytical approaches. [ABSTRACT FROM AUTHOR]