2 research outputs found
Gold nanoparticle-based paper sensor for multiple detection of 12 Listeria spp. by P60-mediated monoclonal antibody
<p>The genus of <i>Listeria</i> consists of heterologous species and its presence in the food chain is an indicator of poor hygiene. However, a portable and simple paper sensor for detection of listeria spp. with high accuracy was still unknown. In this study, we prepared a pair of monoclonal antibodies (mAbs) that specifically recognize the P60 protein on the cell surface of <i>Listeria</i> spp. The selected pair was found to be sensitive to both the P60 protein and cell body of the genus <i>Listeria</i>. On this basis, a rapid paper sensor was established for sensitive <i>Listeria</i> spp. detection. The developed paper sensor broadly cross-reacted with the 12 tested strains of <i>Listeria</i> and the sensitivity in PBS buffer was 10<sup>3</sup>–10<sup>4</sup> colony-forming units (CFU) judged by the gray values of the test line. No cross-reaction with any other gram-positive or gram-negative strains tested was observed. A study using milk samples showed that this paper sensor could detect samples contaminated with low levels of the tested <i>Listeria</i> spp. (1–9 CFU/mL) after 8 h of enrichment and further concentrate for approximately 10 times by centrifugation. The results were in accordance with those obtained using the polymerase chain reaction method.</p
Stabilizing Li<sub>10</sub>SnP<sub>2</sub>S<sub>12</sub>/Li Interface via an in Situ Formed Solid Electrolyte Interphase Layer
Despite the extremely
high ionic conductivity, the commercialization
of Li<sub>10</sub>GeP<sub>2</sub>S<sub>12</sub>-type materials is
hindered by the poor stability against Li metal. Herein, to address
that issue, a simple strategy is proposed and demonstrated for the
first time, i.e., in situ modification of the interface between Li
metal and Li<sub>10</sub>SnP<sub>2</sub>S<sub>12</sub> (LSPS) by pretreatment
with specific ionic liquid and salts. X-ray photoelectron spectroscopy
and electrochemical impedance spectroscopy results reveal that a stable
solid electrolyte interphase (SEI) layer instead of a mixed conducting
layer is formed on Li metal by adding 1.5 M lithium bisÂ(trifluoromethanesulfonyl)Âimide
(LiTFSI)/<i>N</i>-propyl-<i>N</i>-methyl pyrrolidinium
bisÂ(trifluoromethanesulfonyl)Âimide (Pyr<sub>13</sub>TFSI) ionic liquid,
where ionic liquid not only acts as a wetting agent but also improves
the stability at the Li/LSPS interface. This stable SEI layer can
prevent LSPS from directly contacting the Li metal and further decomposition,
and the Li/LSPS/Li symmetric cell with 1.5 M LiTFSI/Pyr<sub>13</sub>TFSI attains a stable cycle life of over 1000 h with both the charge
and discharge voltages reaching about 50 mV at 0.038 mA cm<sup>–2</sup>. Furthermore, the effects of different Li salts on the interfacial
modification is also compared and investigated. It is shown that lithium
bisÂ(fluorosulfonyl) imide (LiFSI) salt causes the enrichment of LiF
in the SEI layer and results in a higher resistance of the cell upon
a long cycling life