Self-propelled affinity biosensors: Moving the receptor around the sample.

Area of Science:

• Nanotechnology
• Biotechnology
• Analytical Chemistry

Background:

• Self-propelled nanomotors offer potential for advanced biosensing.
• Current bioaffinity assays face challenges due to slow analyte transport.
• Novel approaches are needed for efficient recognition and isolation of targets in complex samples.

Purpose of the Study:

• To review recent advances in using catalytic nanomotors for bioaffinity sensing.
• To highlight the use of nanomotors for isolating target biomolecules and cells.
• To discuss how nanomotor propulsion enhances recognition and fluid transport for improved assays.

Main Methods:

• Functionalizing nanomotors with various receptors (antibodies, DNA, aptamers, lectins).
• Utilizing nanomotor movement and microbubble generation for enhanced fluid transport.
• Embedding recognition elements onto or within the nanomotor structure.
• Employing tubular microengines and micromotors with built-in recognition.

Main Results:

• Receptor-functionalized nanomotors enable rapid isolation of targets from biological samples without pre-treatment or washing.
• Nanomotors facilitate 'on-the-fly' recognition events, accelerating the sensing process.
• Enhanced analyte-receptor interactions are achieved through increased fluid transport driven by nanomotor movement.
• Specific examples include isolation of proteins, nucleic acids, and cancer cells.

Conclusions:

• Catalytic nanomotors represent a powerful tool for sensitive bioaffinity sensing and separation.
• These motion-based protocols address limitations of traditional assays by enhancing transport and recognition.
• Nanomotor applications hold promise for diverse biomedical, environmental, and security fields.