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Herein, T4‐bacteriophage‐funcionalizated magnetic Janus micromotors are used for the first time for highly selective Escherichia coli (E. coli) recognition and detection. The micromotors propel at speeds of up to 40 µm s−1 in complex biological samples for on‐the‐fly capture of E. coli "strain B"‐thiolated T4 bacteriophage complex. Detection is achieved by a simplified colorimetric readout in connection with gold nanoparticles. The detection limit meets the cut‐off for the fast diagnosis of urinary tract infections. The bacteriophage‐engineered micromotors are tested on bacteria isolated from urine samples and in serum isolated from negative blood cultures from hospital patients with excellent selectivity and reliability. The new strategy described here holds considerable promise for the multiplexed detection of a myriad of bacteria strains using tailored bacteriophages. Technically, this is the first microplate‐reader integrated micromotor approach, crossing another bridge from the research lab to the practical use of micromotors. Specifically, these results represent a qualitative step forward in the use of micromotor technology with sophisticated functionalization for fast bacteria screening in clinical settings. [ABSTRACT FROM AUTHOR]

Herein, we describe the design of a portable device integrated with micromotors for real-time fluorescence sensing of (bio)markers. The system comprises a universal 3D printed platform to hold a commercial smartphone, which is equipped with an external magnification optical lens (20–400×) and tailor-made emission filters directly attached to the camera, an adjustable sample holder to accommodate a glass slide and laser excitation sources. On a first approach, we illustrate the suitability of the platform using magnetic Janus micromotors modified with fluorescent ZnS@CdxSe1−x quantum dots for real-time ON–OFF mercury detection. On a second approach, graphdiyne tubular catalytic micromotors modified with a rhodamine labelled affinity peptide are used for the OFF–ON detection of cholera toxin B. The micromotor-based smartphone for fluorescence sensing approach was compared to a high-performance optical microscope, and similar analytical features were obtained. This versatility allows for easy integration of micromotor fluorescence sensing strategies based on different propulsion mechanisms, allowing for its future use with a myriad of biomarkers and even multiplexed schemes. [ABSTRACT FROM AUTHOR]

Bacteria monitoring is of paramount significance for healthcare systems worldwide and to assess food or water quality monitoring. In this review, advances during the last 10 years in optical biosensors based on antimicrobial peptides and bacteriophages for bacteria detection are described. Such probes possess high stability which allows for chemical and other modification for highly directed selectivity towards specific bacteria and strain differentiation. The main applications described ranged from clinical diagnosis to food/water quality monitoring as potential vehicles for potential bacterial infections in humans. A brief overview of the advantages and drawbacks of each biosensor for the targeted applications is also given. The high stability and potential for tailored functionalization of antimicrobial peptides and bacteriophages hold considerable promise for the development of the next generation of optical biosensors. [Display omitted] • Antimicrobial peptides and bacteriophages meet smart bacteria detection. • Antimicrobial peptides: stability versus selectivity for optical bacteria detection. • Designing bacteriophages: the route for high selective optical bacteria detection. [ABSTRACT FROM AUTHOR]