呕吐毒素(deoxynivalenol,DON)对人类和动物的健康以及食品经济构成了极大的威胁。该研究建立一种基于金纳米花(gold nanoflowers,AuNFs)的免疫层析试纸条(immunochromatographic test strip,ICTS)快速检测玉米中的呕吐毒素的方法。采...呕吐毒素(deoxynivalenol,DON)对人类和动物的健康以及食品经济构成了极大的威胁。该研究建立一种基于金纳米花(gold nanoflowers,AuNFs)的免疫层析试纸条(immunochromatographic test strip,ICTS)快速检测玉米中的呕吐毒素的方法。采用种子生长法制备了AuNFs,将其与抗DON单克隆抗体结合制备免疫层析试纸条中的金标探针,并对pH值、抗体量、上样缓冲液浓度、检测线(test-line,T线)浓度和金标探针量进行优化,最终用于玉米中的DON检测。经过优化实验条件,确定了最优pH值为7.5,最佳抗体添加量为1μL,最适上样缓冲液浓度为PBST+1%PVP K30,最好的T线质量浓度为0.1 mg/mL以及最佳探针量为3μL。在最优反应体系下,实验结果可以通过肉眼观察进行定性分析,该方法检出限为20μg/kg,灵敏度≥99%、假阳性率≤1%、假阴性率≤1%,且与现有标准方法检测结果一致,同时与其他真菌毒素无交叉反应。以AuNFs标记抗体为探针制备的ICTS灵敏度高,特异性强,可以实现玉米中DON的快速检测。展开更多
We present a comprehensive investigation into the superconducting properties of L_(a3)Al,a La-based metal with a kagome structure.L_(a3)Al crystallizes in a Ni_(3)Sn-type crystal structure(space group P63/mmc),where t...We present a comprehensive investigation into the superconducting properties of L_(a3)Al,a La-based metal with a kagome structure.L_(a3)Al crystallizes in a Ni_(3)Sn-type crystal structure(space group P63/mmc),where the La atoms form a kagome lattice.Resistivity measurements reveal superconducting transition with T_(c)^(onset)=6.37 K and Tczero=6.18 K.In magnetic susceptibility measurements,the superconducting transition is observed at 6.16 K.The lower and upper critical fields are determined to be 22.17 mT and 6.69 T,respectively.Heat capacity measurements confirm the bulk superconductivity,showing a normalized specific heat change of△Ce/(_(γ)T_(c))=2.16 and an electron-phonon coupling strength ofλ_(ep)=0.92.DFT calculations reveal the intricate band structure of La_(3)Al.The notable specific heat jump,coupled with the electron-phonon coupling strengthλ_(ep),indicates that La_(3)Al exhibits characteristics of an intermediately coupled type-Ⅱsuperconductor.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52272268 and 52250308)the Strategic Priority Research Program and Key Research Program of Frontier Sciences of the Chinese Academy of Sciences(Grant No.XDB33010100)+1 种基金the Informatization Plan of Chinese Academy of Sciences(Grant No.CAS-WX2021SF0102)the Synergetic Extreme Condition User Facility(SECUF)。
文摘We present a comprehensive investigation into the superconducting properties of L_(a3)Al,a La-based metal with a kagome structure.L_(a3)Al crystallizes in a Ni_(3)Sn-type crystal structure(space group P63/mmc),where the La atoms form a kagome lattice.Resistivity measurements reveal superconducting transition with T_(c)^(onset)=6.37 K and Tczero=6.18 K.In magnetic susceptibility measurements,the superconducting transition is observed at 6.16 K.The lower and upper critical fields are determined to be 22.17 mT and 6.69 T,respectively.Heat capacity measurements confirm the bulk superconductivity,showing a normalized specific heat change of△Ce/(_(γ)T_(c))=2.16 and an electron-phonon coupling strength ofλ_(ep)=0.92.DFT calculations reveal the intricate band structure of La_(3)Al.The notable specific heat jump,coupled with the electron-phonon coupling strengthλ_(ep),indicates that La_(3)Al exhibits characteristics of an intermediately coupled type-Ⅱsuperconductor.
