Search

The rapid, simple, and reliable identification of the most prevalent pathogens is essential for clinical diagnostics, biology, and food safety. Herein, four protein-encapsulated gold nanoclusters (protein-AuNCs) are designed and prepared as a sensor array for rapid identification of bacteria. The discrimination of six kinds of bacteria, including two kinds of drug-resistant bacteria, is successfully realized by the as-fabricated sensor array. The strategy presented here shows the advantages of easy synthesis and convenient to use. Furthermore, 100% classification accuracy is achieved by the sensor array consisting of two protein-AuNCs probes, demonstrating the design with sufficient diagnostic capacity. Taken together, the developed sensor array holds great promise for facile diagnosis of bacterial infection in resource-limited settings., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A powerful strategy for long-term and diffusional-resistance-minimized whole-cell biocatalysis in biphasic systems is reported where individually encapsulated bacteria are employed as robust and recyclable Pickering interfacial biocatalysts. By individually immobilizing bacterial cells and optimizing the hydrophobic/hydrophilic balance of the encapsulating magnetic mineral shells, the encased bacteria became interfacially active and locate at the Pickering emulsion interfaces, leading to dramatically enhanced bioconversion performances by minimizing internal and external diffusional resistances. Moreover, in situ product separation and biocatalyst recovery was readily achieved using a remote magnetic field. Importantly, the mineral shell effectively protected the entire cell from long-term organic-solvent stress, as shown by the reusability of the biocatalysts for up to 30 cycles, while retaining high stereoselective catalytic activities, cell viabilities, and proliferative abilities., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Extracellular DNA (eDNA) is an essential structural component during biofilm formation, including initial bacterial adhesion, subsequent development, and final maturation. Herein, the construction of a DNase-mimetic artificial enzyme (DMAE) for anti-biofilm applications is described. By confining passivated gold nanoparticles with multiple cerium(IV) complexes on the surface of colloidal magnetic Fe3O4 /SiO2 core/shell particles, a robust and recoverable artificial enzyme with DNase-like activity was obtained, which exhibited high cleavage ability towards both model substrates and eDNA. Compared to the high environmental sensitivity of natural DNase in anti-biofilm applications, DMAE exhibited a much better operational stability and easier recoverability. When DMAE was coated on substratum surfaces, biofilm formation was inhibited for prolonged periods of time, and the DMAE excelled in the dispersion of established biofilms of various ages. Finally, the presence of DMAE remarkably potentiated the efficiency of traditional antibiotics to kill biofilm-encased bacteria and eradiate biofilms. [ABSTRACT FROM AUTHOR]

The biofilm resistance of microorganisms has severe economic and environmental implications, especially the contamination of facilities associated with human life, including medical implants, air-conditioning systems, water supply systems, and food-processing equipment, resulting in the prevalence of infectious diseases. Once bacteria form biofilms, their antibiotic resistance can increase by 10–1,000-fold, posing a great challenge to the treatment of related diseases. In order to overcome the contamination of bacterial biofilm, destroying the biofilm's matrix so as to solve the penetration depth dilemma of antibacterial agents is the most effective way. Here, a magnetically controlled multifunctional micromotor was developed by using H 2 O 2 as the fuel and MnO 2 as the catalyst to treat bacterial biofilm infection. In the presence of H 2 O 2 , the as-prepared motors could be self-propelled by the generated oxygen microbubbles. Thereby, the remotely controlled motors could drill into the EPS of biofilm and disrupt them completely with the help of bubbles. Finally, the generated highly toxic •OH could efficiently kill the unprotected bacteria. This strategy combined the mechanical damage, highly toxic •OH, and precise magnetic guidance in one system, which could effectively eliminate biologically infectious fouling in microchannels within 10 min, possessing a wide range of practical application prospects especially in large scale and complex infection sites. [Display omitted] • Mechanical damage, highly toxic •OH, and precise magnetic guidance were integrated in one antimicrobial system. • H 2 O 2 was used as the fuel to trigger the high-speed movement of motor and serve as the source of high toxic •OH. • Enhanced antibacterial activities were obtained even for the treatment of drug-resistant bacteria MRSA. • The micro-nano hybrid multifunctional motors developed here are precisely controlled and deeply penetrated. • Motors have strong destructive ability for the treatment of large-scale biofilm EPS even at complex infection sites. [ABSTRACT FROM AUTHOR]