Ag–Polymer Nanocomposites for Capture, Detection, and Destruction of Bacteria

Abstract

Bacterial infection is one of the major problems for human health. To prevent outbreak of bacteria-caused diseases, early diagnosis of bacterial pathogen and effective destruction of pathogenic microorganisms are in urgent need. In this work, we developed a new multifunctional nanocomposite material that can effectively capture and destroy bacteria. Epoxide-modified nanoparticles were synthesized by microemulsion polymerization and precipitation polymerization. The epoxide groups on the particle surface were reacted with polyethylenimine to introduce cationic amine groups. The amine groups on the nanoparticle surface enhanced the colloidal stability of the particles’ suspension and provided multivalent interactions to bind and destroy the bacteria. After further modification with Ag nanoparticles, the final composite nanomaterial was able to not only capture and destroy Gram-negative bacteria but also allow the bacteria’s fingerprint spectra to be obtained through surface-enhanced Raman scattering. The multifunctional nanoparticles developed in this work offer a new approach toward fast capture, detection, and destruction of pathogenic bacteria.

Positively-charged plasmonic nanostructures for SERS sensing applications

“…Therefore, great efforts have been devoted to the fabrication of larger and homogeneous plasmonic NPs via, among others, seed-mediated approaches. For instance, the direct synthesis of well-dened polyhedral gold nanoparticles with various sizes (38,40, and 50 nm) using PEI as a capping molecule has been successfully achieved using preformed PEI-coated gold seeds of 9 nm. Size tuning was achieved by combining different amounts of seed to a growth solution containing HAuCl 4 and PEI (ascorbic acid was employed as the reducing agent).…”

“…; bacteria, fungi), adopting diverse indirect 96,97 and direct sensing strategies, along with positively-charged nanoparticles. 27,34,[38][39][40]46,47,50,51,75 A representative workow to carry out direct SERS analysis of pathogens using AgNPs is outlined in Fig. 8A.…”

“…To this end, PGMA NPs were previously coated with PEI to modify the nanoparticle charge to further grow Ag nanoparticles on the surface by adding a AgNO 3 solution and NaBH 4 . 40 …”

Recent trends and advances in polyindole-based nanocomposites as potential antimicrobial agents: a mini review

“…, Ag nanoparticles and the polymers, such as strong antimicrobial effect of nano Ag, unique features of polymers such as exceptional structural consistency, various morphologies and architecture and varying chemical compositions, leads to the development of a composite systems with improved properties. 95–97…”

Point of Care Sensors for Infectious Pathogens

“…The pH or enzyme triggering mode of dye-based sensors typically means they struggle to support high levels of selectivity. − Nanomaterial-based sensors, on the contrary, can exhibit a strong pathogen-specific response by virtue of an induced aggregation of receptor modified dispersed nanomaterial. , Magnetic, gold, silver, and copper nanoparticles have been applied within derived pathogen sensors and make use of their natively high target capture efficiency . Gold and silver nanoparticles are particularly potent in such approaches because of the very strong aggregation-sensitive colorimetric changes supported by their plasmonic characteristics. , Such plasmonic colorimetric sensors have now been widely investigated within rapid (a few minutes) yes/no pathogen tests and are capable of supporting the detection of bacterial nucleic acids, − virus particles, , endotoxins, − and pathogen-specific protein markers. , …”