Fluorescent aptasensor was developed for acrylamide(AAm)detection by utilizing the adsorption effect of Au nanoparticles(AuNPs)and fluorescence properties of SYBR Green I(SGI)towards double-stranded DNA(dsDNA).Compare...Fluorescent aptasensor was developed for acrylamide(AAm)detection by utilizing the adsorption effect of Au nanoparticles(AuNPs)and fluorescence properties of SYBR Green I(SGI)towards double-stranded DNA(dsDNA).Compared to the binding of aptamer with AAm,the higher affinity of aptamer with cDNA may facilitate a structure switching from the aptamer/AAm complex to aptamer/cDNA dsDNA.The free aptamers were adsorbed onto AuNPs and separated by centrifugation.Subsequently,SGI was introduced as a fluorescent reporter for quantitative detection.Compared to conventional AuNPs-based colorimetric detection,the sensitivity of this strategy was improved by 3.18-fold in the range of 0.005–50 mg/L with a low detection limit of 4.68μg/L.The method has been successfully applied to analyze fried twists and biscuits.Notably,it is a low-cost and general method that provides guidance for the development of rapid screening technology in the field.展开更多
通过对湖南沃溪Au-Sb-W矿床鱼儿山-红岩溪矿段中黑钨矿族矿物的野外观察表明，含黑钨矿族矿物的矿石主要呈条带状、细脉状，次为浸染状构造，结构上主要为半自形-它形板状和柱状；X射线粉晶衍射结果得出其物相为钨铁矿，晶胞参数为a0：4...通过对湖南沃溪Au-Sb-W矿床鱼儿山-红岩溪矿段中黑钨矿族矿物的野外观察表明，含黑钨矿族矿物的矿石主要呈条带状、细脉状，次为浸染状构造，结构上主要为半自形-它形板状和柱状；X射线粉晶衍射结果得出其物相为钨铁矿，晶胞参数为a0：4.7454 A ，b0：5.7160A ，c0：4.9753 A ，β：90°13′；电子探针分析结果显示，MnO含量范围0.97%-11%，FeO含量范围13.65%-23.36%，WO3含量范围71.39%-76.87%，既有高MnO含量亦有低MnO含量的钨铁矿，成连续性变化，并从深部中段向浅部中段，MnO含量具有增大趋势。计算其晶体化学式为（Fe0.57-1.02Mn0.46-0.04）W0.98-1.00O4。相关分析得出FeO与MnO相关系数为-0.98，WO3与MnO相关系数为0.47，WO3与FeO相关系数为-4.10。黑钨矿族矿物中Nb和Ta的含量较低，暗示了沃溪Au-Sb-W矿床可能为沉积-改造热液成因。展开更多
In the northwestern margin of the Youjiang basin(NWYB)in SW China,many Carlin-like gold deposits are highly antimony(Sb)-rich,and many vein-type Sb deposits contain much Au.These deposits have similar ages,host rocks,...In the northwestern margin of the Youjiang basin(NWYB)in SW China,many Carlin-like gold deposits are highly antimony(Sb)-rich,and many vein-type Sb deposits contain much Au.These deposits have similar ages,host rocks,ore-forming temperatures,ore-related alterations and ore mineral assemblages,but the Au and Sb metallogenic relations and their ore-forming process remain enigmatic.Here we investigate the large Qinglong Sb deposit in the NWYB,which has extensive sub-economic Au mineralization,and present a new metallogenic model based on in-situ trace elements(EPMA and LA-ICP-MS)and sulfur isotopes(NanoSIMS and fs-LA-MC-ICPMS)of the ore sulfides.At Qinglong,economic Sb ores contain coarse-grained stibnite,jasperoid quartz and fluorite,whilst the sub-economic Au–Sb ores comprise dominantly veined quartz,arsenian pyrite and fine-grained stibnite.Three generations of ore-related pyrite(Py1,Py2 and Py3)and two generations of stibnite(Stb1 and Stb2)are identified based on their texture,chemistry,and sulfur isotopes.The pre-ore Py1 is characterized by the lower ore element(Au,As,Sb,Cu and Ag)contents(mostly below the LA-ICP-MS detection limit)and Co/Ni ratios(average 0.31)than the ore-stage pyrites(Py2 and Py3),implying a sedimentary/diagenetic origin.The Py2 and Py3 have elevated ore element abundance(maximum As=6500 ppm,Au=22 ppm,Sb=6300 ppm,Cu=951 ppm,Ag=77 ppm)and Co/Ni ratios(average 1.84),and have positive As vs.Au–Sb–Cu–Ag correlations.Early-ore Stb1 has lower As(0.12–0.30 wt.%)than late-ore Stb2(0.91–1.20 wt.%).These features show that the progressive As enrichment in ore sulfides is accompanied by increasing Au,Sb,Cu and Ag with the hydrothermal evolution,thereby making As a good proxy for Au.As-rich,As-poor and As-free zones are identified via NanoSIMS mapping of the Au-bearing pyrite.The As-rich zones in the Qinglong Au-bearing pyrites(Py2 and Py3)and ore stibnites(Stb1 and Stb2)have narrowδ^(34)SH_(2)S ranges(-8.9‰to +4.1‰,average-3.1‰)and-2.9‰to +6.9‰,average + 1.3‰),respectively,indicating that the Au-rich and Sb-rich fluids may have had the same sulfur source.Published in-situ sulfur isotopic data of pyrite As-rich zones from other Carlin-like Au deposits(Shuiyindong,Taipingdong,Nayang,Getang and Lianhuashan)in the NWYB have similar ore-fluidδSH_(2)S values(-4.5‰to +6.7‰,average-0.6‰)to those of Qinglong.Therefore,we infer that the sulfur of both Au and Sb mineralization was derived from the same magmatic-related source(0±5‰)in the NWYB.Moreover,the core of pyrites(Py1)has variable S isotope fractionation(-18.9‰to +18.1‰,mostly +3‰to +12‰),suggesting that the higher-^(34)S H_(2)S was produced by bacterial sulfate reduction(BSR).The hydrothermal pyrite(Py2 and Py3)δ^(34)S values gradually decrease with increasing As concentrations,and ultimately,within the restricted range(-5‰to +5‰)in As-rich zones.This variation implies that the As-rich pyrite was formed through ongoing interactions of the magmatic-hydrothermal fluid with pre-existing sedimentary pyrites,causing the progressive decreasing δ^(34)S values with As content increase,Hence,the fluid/mineral interaction may have generated the observed variation in δ^(34)S and As contents.Overall,comparing the Au and Sb deposits in the NWYB,we favor a magmatic-related source for the Au–Sb–As-rich fluids,but the Au-and Sb-ore fluids were likely evolved at separate stages in the ore-forming system.展开更多
基金supported by Science and Technology Development Program of Jilin Province,China(No.20210509024RQ)On-budget Capital Construction Fund of Jilin Province Development and Reform Commission,China(2023C014)+1 种基金Graduate Innovation Fund of Jilin University,China(No.2022051)College Students'Innovative Entrepreneurial Training Plan Program of Jilin University,China(S202210183292).
文摘Fluorescent aptasensor was developed for acrylamide(AAm)detection by utilizing the adsorption effect of Au nanoparticles(AuNPs)and fluorescence properties of SYBR Green I(SGI)towards double-stranded DNA(dsDNA).Compared to the binding of aptamer with AAm,the higher affinity of aptamer with cDNA may facilitate a structure switching from the aptamer/AAm complex to aptamer/cDNA dsDNA.The free aptamers were adsorbed onto AuNPs and separated by centrifugation.Subsequently,SGI was introduced as a fluorescent reporter for quantitative detection.Compared to conventional AuNPs-based colorimetric detection,the sensitivity of this strategy was improved by 3.18-fold in the range of 0.005–50 mg/L with a low detection limit of 4.68μg/L.The method has been successfully applied to analyze fried twists and biscuits.Notably,it is a low-cost and general method that provides guidance for the development of rapid screening technology in the field.
文摘通过对湖南沃溪Au-Sb-W矿床鱼儿山-红岩溪矿段中黑钨矿族矿物的野外观察表明，含黑钨矿族矿物的矿石主要呈条带状、细脉状，次为浸染状构造，结构上主要为半自形-它形板状和柱状；X射线粉晶衍射结果得出其物相为钨铁矿，晶胞参数为a0：4.7454 A ，b0：5.7160A ，c0：4.9753 A ，β：90°13′；电子探针分析结果显示，MnO含量范围0.97%-11%，FeO含量范围13.65%-23.36%，WO3含量范围71.39%-76.87%，既有高MnO含量亦有低MnO含量的钨铁矿，成连续性变化，并从深部中段向浅部中段，MnO含量具有增大趋势。计算其晶体化学式为（Fe0.57-1.02Mn0.46-0.04）W0.98-1.00O4。相关分析得出FeO与MnO相关系数为-0.98，WO3与MnO相关系数为0.47，WO3与FeO相关系数为-4.10。黑钨矿族矿物中Nb和Ta的含量较低，暗示了沃溪Au-Sb-W矿床可能为沉积-改造热液成因。
基金the National Natural Science Foundation of China(Grant No.41802107)Guizhou Scientific and Technology Fund(Grant No.QKHJC[2019]1315+2 种基金QKHJC[2019]1149H)China Postdoctoral Science Foundation(Grant No.2019M653495)the Talent Introduction Project of Guizhou University(Grant No.201772).
文摘In the northwestern margin of the Youjiang basin(NWYB)in SW China,many Carlin-like gold deposits are highly antimony(Sb)-rich,and many vein-type Sb deposits contain much Au.These deposits have similar ages,host rocks,ore-forming temperatures,ore-related alterations and ore mineral assemblages,but the Au and Sb metallogenic relations and their ore-forming process remain enigmatic.Here we investigate the large Qinglong Sb deposit in the NWYB,which has extensive sub-economic Au mineralization,and present a new metallogenic model based on in-situ trace elements(EPMA and LA-ICP-MS)and sulfur isotopes(NanoSIMS and fs-LA-MC-ICPMS)of the ore sulfides.At Qinglong,economic Sb ores contain coarse-grained stibnite,jasperoid quartz and fluorite,whilst the sub-economic Au–Sb ores comprise dominantly veined quartz,arsenian pyrite and fine-grained stibnite.Three generations of ore-related pyrite(Py1,Py2 and Py3)and two generations of stibnite(Stb1 and Stb2)are identified based on their texture,chemistry,and sulfur isotopes.The pre-ore Py1 is characterized by the lower ore element(Au,As,Sb,Cu and Ag)contents(mostly below the LA-ICP-MS detection limit)and Co/Ni ratios(average 0.31)than the ore-stage pyrites(Py2 and Py3),implying a sedimentary/diagenetic origin.The Py2 and Py3 have elevated ore element abundance(maximum As=6500 ppm,Au=22 ppm,Sb=6300 ppm,Cu=951 ppm,Ag=77 ppm)and Co/Ni ratios(average 1.84),and have positive As vs.Au–Sb–Cu–Ag correlations.Early-ore Stb1 has lower As(0.12–0.30 wt.%)than late-ore Stb2(0.91–1.20 wt.%).These features show that the progressive As enrichment in ore sulfides is accompanied by increasing Au,Sb,Cu and Ag with the hydrothermal evolution,thereby making As a good proxy for Au.As-rich,As-poor and As-free zones are identified via NanoSIMS mapping of the Au-bearing pyrite.The As-rich zones in the Qinglong Au-bearing pyrites(Py2 and Py3)and ore stibnites(Stb1 and Stb2)have narrowδ^(34)SH_(2)S ranges(-8.9‰to +4.1‰,average-3.1‰)and-2.9‰to +6.9‰,average + 1.3‰),respectively,indicating that the Au-rich and Sb-rich fluids may have had the same sulfur source.Published in-situ sulfur isotopic data of pyrite As-rich zones from other Carlin-like Au deposits(Shuiyindong,Taipingdong,Nayang,Getang and Lianhuashan)in the NWYB have similar ore-fluidδSH_(2)S values(-4.5‰to +6.7‰,average-0.6‰)to those of Qinglong.Therefore,we infer that the sulfur of both Au and Sb mineralization was derived from the same magmatic-related source(0±5‰)in the NWYB.Moreover,the core of pyrites(Py1)has variable S isotope fractionation(-18.9‰to +18.1‰,mostly +3‰to +12‰),suggesting that the higher-^(34)S H_(2)S was produced by bacterial sulfate reduction(BSR).The hydrothermal pyrite(Py2 and Py3)δ^(34)S values gradually decrease with increasing As concentrations,and ultimately,within the restricted range(-5‰to +5‰)in As-rich zones.This variation implies that the As-rich pyrite was formed through ongoing interactions of the magmatic-hydrothermal fluid with pre-existing sedimentary pyrites,causing the progressive decreasing δ^(34)S values with As content increase,Hence,the fluid/mineral interaction may have generated the observed variation in δ^(34)S and As contents.Overall,comparing the Au and Sb deposits in the NWYB,we favor a magmatic-related source for the Au–Sb–As-rich fluids,but the Au-and Sb-ore fluids were likely evolved at separate stages in the ore-forming system.
