Chiral Upconversion Heterodimers for Quantitative Analysis and Bioimaging of Antibiotic‐Resistant Bacteria In Vivo

Abstract

Heterodimers of upconversion nanoparticles (UCNPs) and gold yolk–shell nanoparticles are fabricated for the quantification of polymyxin‐B‐resistant Escherichia coli. They produce two signals, circular dichroism (CD) and upconversion luminescence (UCL). Interestingly, due to the different affinity of polymyxin B for sensitive and resistant strain, as the concentration of polymyxin B increases, the amount of UCNPs in sensitive bacteria increases sharply, increasing the intracellular UCL signal at a low polymyxin B concentration immobilized on the UCNP. The CD intensity is correspondingly reduced as the amount of UCNPs in solution decreased. Meanwhile, for polymyxin‐B‐resistant strain, the intracellular UCL increases slowly even in a high polymyxin B concentration, and the CD intensity in solution is also enhanced because of the inefficient entering of UCNP. Therefore, based on the concentration of polymyxin B coupled to the UCNPs, the levels of polymyxin‐B‐resistant bacteria can be detected with dual signals. Importantly, with 980 nm irradiation, both polymyxin‐B‐sensitive strains and polymyxin‐resistant bacteria used to induce infection in mice are detected with UCL imaging in vivo and treated well with photodynamic therapy. This novel dual‐mode heterodimer has potential utility for the advanced surveillance and control of drug‐resistant bacteria.

Effect of dietary supplementation with hyperimmunized hen egg yolk powder on diarrhoea incidence and intestinal health of weaned pigs

“…To solve these post-weaning problems, antibiotics have been widely used in the animal feed industry as growth promoters and a medicated feed additive to reduce susceptibility to infectious disease (Vondruskova et al, 2010). Unfortunately, widespread use or misuse of antibiotics has resulted in increasing multiple antimicrobial resistance and antibiotic residue in edible animal products (Sun et al, 2018;Liu et al, 2017;Han et al, 2016). Hence, safe, natural and effective products have been studied extensively as alternatives to antibiotic feed additives.…”

Engineering of chiral nanomaterials for biomimetic catalysis

“…40 In the past decades, many asymmetric configurations of chiral assemblies have been reported based on DNA techniques, such as dimers, trimers, pyramidal assemblies and helix structures. [41][42][43][44] Recently, a series of well-designed hierarchically programmed chiral nanoassemblies were reported (Fig. 3).…”

Chiral Nanoprobes and Their Biological Effects

“…Simple and fast biosensor systems based on dimers have been established for detecting the level of antibiotic resistance (Figure 4). [ 14 ] Due to the different affinity of polymyxin B to sensitive and resistant strains, chiral heterodimers were designed by antigen‐ antibody reaction, and the resistance of Escherichia coli to polymyxin B was detected by a dual signal in the circular dichroism (CD) spectrum and up‐conversion luminescence (UPL). Our work showed that due to the strong affinity of polymyxin B to the sensitive strain, the polymyxin B‐modified up‐conversion nanoparticles (UCNPs) on the surface can rapidly enter sensitive bacteria.…”