Sensitive Monitoring of Enterobacterial Contamination of Food Using Self-Propelled Janus Microsensors

Nanoparticles for Signaling in Biodiagnosis and Treatment of Infectious Diseases

Advances in nanoparticle-based systems constitute a promising research area with important implications for the treatment of bacterial infections, especially against multidrug resistant strains and bacterial biofilms. Nanosystems may be useful for the diagnosis and treatment of viral and fungal infections. Commercial diagnostic tests based on nanosystems are currently available. Different methodologies based on nanoparticles (NPs) have been developed to detect specific agents or to distinguish between Gram-positive and Gram-negative microorganisms. Also, biosensors based on nanoparticles have been applied in viral detection to improve available analytical techniques. Several point-of-care (POC) assays have been proposed that can offer results faster, easier and at lower cost than conventional techniques and can even be used in remote regions for viral diagnosis. Nanoparticles functionalized with specific molecules may modulate pharmacokinetic targeting recognition and increase anti-infective efficacy. Quorum sensing is a stimuli-response chemical communication process correlated with population density that bacteria use to regulate biofilm formation. Disabling it is an emerging approach for combating its pathogenicity. Natural or synthetic inhibitors may act as antibiofilm agents and be useful for treating multi-drug resistant bacteria. Nanostructured materials that interfere with signal molecules involved in biofilm growth have been developed for the control of infections associated with biofilm-associated infections.

Chemical micromotors self-assemble and self-propel by spontaneous symmetry breaking

Propelling chemical dimer motors can spontaneously self-assemble from isotropic non-propelling colloids.

A disposable microcapsule array chip fabricated by ice printing combined with isothermal amplification for Salmonella DNA detection

In this work, a novel microcapsule array chip was fabricated for the detection of Salmonella DNA by integrating an ice-printing technique with DNA isothermal amplification. Reaction solutions were previously sealed in the microcapsule array chip via ice printing. To protect the relatively fragile DNA isothermal amplification system, an extra polystyrene (PS) film was introduced to isolate the reaction solution from photopolymer precursor, which was proved to be a vital step for providing a clean and stable environment for DNA amplification reaction. Detection operation can be done by simply injecting sample DNA into the microcapsule by an easily accessible syringe, and the result can be directly obtained through color change within 90 minutes. This method shows good sensitivity, specificity and stability.

An ice printing fabricated microcapsule array chip is demonstrated based on loop-mediated isothermal amplification for visual salmonella DNA detection.