Review of Optical Fiber Optofluidic Chemical Sensors and Biosensors

Abstract

Optical fiber sensors have gained significant attention in recent years owing to their remarkable advantages of remote operation and rapid response. The integration of optical fiber sensing with the microfluidics technology has paved the way for the establishment of optical fiber optofluidic sensing. Optical fiber optofluidic systems possess the advantages of the low invasiveness, compact structure, excellent biocompatibility, and the ability to handle small analyte volumes, rendering them particularly suitable for serving as chemical sensors and biosensors. In this paper, we present an in-depth overview of optical fiber optofluidic chemical sensors and biosensors. Firstly, we provide a comprehensive summary of the types of optical fibers commonly employed in optofluidic chemical and biosensing, elucidating their distinct attributes and performance characteristics. Subsequently, we introduce and thoroughly analyze several representative sensing mechanisms employed in optical fiber optofluidic systems and main performance parameters. Furthermore, this review delves into the modification and functionalization of optical fibers. Additionally, we showcase typical biosensing and chemical sensing applications to demonstrate the practicality and versatility of optical fiber optofluidic sensing. Finally, the conclusion and outlook are given.

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