摘要
抽象图像
构建了一种用于抗生素抗性基因（ARGs）检测的智能温度刺激驱动的多重光电化学（PEC）分析，其中通过调节“货物”的选择性释放，刺激响应性门控允许同时检测多种四环素抗性基因，使用tetA（TDNA1）和tetC（TDNA 2）作为模型。在PEC生物测定中嵌入了双温度响应纳米组件作为信号DNA阶段：一种热响应聚合物（聚（N-异丙基丙烯酰胺），PNIPAM）封端的介孔二氧化硅纳米颗粒（MSN），其负载HgO纳米颗粒的“货物”作为信号DNA1标签(SDNA1-PNIPAM@MSN@HgONPs）和其他酒石酸锑（SbT）锚定的二氧化硅纳米球作为信号DNA2标签(SDNA2-SbT@SiO2NSs). 在20°C，低于PNIPAM的较低临界溶液温度（LCST）时SDNA1-PNIPAM@MSN@HgONPs处于ON状态，通过SiO2的孔点燃Hg2+的释放。在高于LCST（40°C）时，它处于关闭状态。同样，SbT的热依赖性解离赋予了接枝的SDNA2标签从OFF（在20°C下）切换到ON（在40°C）状态，从而引发SbO+的释放。由于光活性层的结构演变为HgS/ZnS或Sb2S3/ZnS异质结构，释放的Hg2+和SbO+触发了放大的光电流，从而实现了对多种ARGs的灵敏检测：tetA、tetC、tetG、tetM、tetO、tetZ、tetX和tetW。结合热图分析，可以实现对12个样本中ARGs图谱的快速筛选。这种生物测定方法简单且可用于多基因分析，检测限低至0.50nM。并成功应用于实际污泥样品中四环素ARGs的测定。
Abstract
Abstract Image
A smart temperature stimuli-driven multiplex photoelectrochemical (PEC) assay was constructed for antibiotic resistance genes (ARGs) detection, where the stimuli-responsive gatekeeping by regulating the alternative release of “cargo” allowed for the simultaneous detection of multiple tetracycline resistance gene, using tetA (TDNA1) and tetC (TDNA2) as the model. Dual temperature-responsive nanoassemblies were embedded in the PEC bioassay as signal DNA tages: one thermoresponsive polymer (poly(N-isopropylacrylamide), PNIPAM)-capped mesoporous silica nanoparticles (MSN) with loading the “cargo” of HgO nanoparticles as signal DNA1 tags (SDNA1-PNIPAM@MSN@HgONPs) and the other antimony tartrate (SbT)-anchored silica nanospheres as signal DNA2 tags (SDNA2-SbT@SiO2NSs). At 20 °C, below the lower critical solution temperature (LCST) of PNIPAM, the “gatekeeper” PNIPAM in SDNA1-PNIPAM@MSN@HgONPs was in an ON state, igniting Hg2+ release through the pore of SiO2. While at above LCST (40 °C), it was in an OFF state. Likewise, the thermo-dependent dissociation of SbT endowed the grafted SDNA2 tags switching from the OFF (at 20 °C) to ON state (at 40 °C), igniting SbO+ release. The released Hg2+ and SbO+ triggered the amplified photocurrents due to the structure evolution of the photoactive layer into HgS/ZnS or Sb2S3/ZnS heterostructure, thus achieving sensitive detection of multiple ARGs: tetA, tetC, tetG, tetM, tetO, tetZ, tetX, and tetW. Combined with heat map analysis, rapid screening of the ARGs profiles in 12 samples could be realized. This bioassay is simple and accessible for multiple genes analysis with the detection limit down to 0.50 nM. And it was successfully applied for measuring tetracycline ARGs in real sludge samples.

https://pubs.acs.org/doi/abs/10.1021/acs.analchem.2c03698