Emerging Roles of Microrobots for Enhancing the Sensitivity of Biosensors

Abstract

To meet the increasing needs of point-of-care testing in clinical diagnosis and daily health monitoring, numerous cutting-edge techniques have emerged to upgrade current portable biosensors with higher sensitivity, smaller size, and better intelligence. In particular, due to the controlled locomotion characteristics in the micro/nano scale, microrobots can effectively enhance the sensitivity of biosensors by disrupting conventional passive diffusion into an active enrichment during the test. In addition, microrobots are ideal to create biosensors with functions of on-demand delivery, transportation, and multi-objective detections with the capability of actively controlled motion. In this review, five types of portable biosensors and their integration with microrobots are critically introduced. Microrobots can enhance the detection signal in fluorescence intensity and surface-enhanced Raman scattering detection via the active enrichment. The existence and quantity of detection substances also affect the motion state of microrobots for the locomotion-based detection. In addition, microrobots realize the indirect detection of the bio-molecules by functionalizing their surfaces in the electrochemical current and electrochemical impedance spectroscopy detections. We pay a special focus on the roles of microrobots with active locomotion to enhance the detection performance of portable sensors. At last, perspectives and future trends of microrobots in biosensing are also discussed.

Acoustic Actuators for the Manipulation of Micro/Nanorobots: State-of-the-Art and Future Outlooks

“…In contrast to conventional robots, MNRs can access very small areas that have never been observed previously, such as microchannels [1][2][3][4][5] and microvessels [6]. MNRs have demonstrated immense potential for utilization in a variety of biomedical applications, encompassing areas such as chemical detection [7,8], biosensing [9][10][11][12], and microsurgery. The rapid development of MNRs manufacturing technologies in recent decades has significantly propelled the evolution of autonomous robotic systems which have become valuable technologies for healthcare as well as in biotechnology, biomedical engineering, and life sciences.…”