While engineered nanoparticles are widely used and maybe eventually released into the environment,natural nanoparticles are also commonly found in the Earth system.Nanoparticles may critically affect the geochemical m...While engineered nanoparticles are widely used and maybe eventually released into the environment,natural nanoparticles are also commonly found in the Earth system.Nanoparticles may critically affect the geochemical migration of associated elements and pose potential threats to the ecological environment.It is necessary to establish an accurate and reliable method for measuring the concentration of nanoparticles.AAS is one of the most commonly used methods for the concentration determination of nanoparticles.However,till now,there has been no systematic report on how experimental variables affect AAS measurements.In this study,we used gold nanoparticles(AuNPs) as an example and studied the influences of a list of factors on the concentration determination of AuNPs by AAS,including digestion method,ionization interference,acidic medium,background correction method,and organic matter.We demonstrate that all these factors may have varying degrees of influence on the measured gold concentrations.When the gold colloid is digested at room temperature for more than 8 h or at 60℃ for more than 2 h,and the system contains a low concentration of organic matter,AAS can accurately measure the AuNP concentration at ppm-level.The deuterium lamp background deduction method is not recommended to use for samples with lower gold concentrations.展开更多
Ginger (<i><span>Zingiber officinale</span></i><span>) is an important spice and medicinal plant used in different parts of the world. The objective of current study was to determine the ...Ginger (<i><span>Zingiber officinale</span></i><span>) is an important spice and medicinal plant used in different parts of the world. The objective of current study was to determine the level of essential and non-essential metals in ginger and its correlation with concentration of metals in the supporting soil. The level of K, Na, Ca, Mg, Mn, Fe, Zn, Cu, Co, Cd and Pb in soil and ginger cultivated in the selected districts of Wolaita zone, Southern Ethiopia were determined using flame atomic absorption spectrometry. A 0.5 g ginger sample was digested using a mixture of 4 ml HNO</span><sub><span style="vertical-align:sub;">3</span></sub><span> and 1.5 ml HClO</span><sub><span style="vertical-align:sub;">4</span></sub><span> at 210°</span><span>C</span><span> for 150 min</span><span>utes, and a 0.5 g soil sample was digested employing a mixture of 6 ml aqua-regia and 1 ml H</span><sub><span style="vertical-align:sub;">2</span></sub><span>O</span><sub><span style="vertical-align:sub;">2</span></sub><span> at 280°</span><span>C</span><span> for 150 minutes. The metal</span><span> concentrations range in dry weight basis for ginger samples is decreasing in the order: K (1691 </span><span>-</span><span> 3487 mg/kg) > Mg (701 </span><span>-</span><span> 1583 mg/kg) > Ca (862 </span><span>-</span><span> 1476 mg/kg) > Na (398 </span><span>-</span><span> 776 mg/kg) > Mn (325 </span><span>-</span><span> 672 mg/kg) > Fe (6.14 </span><span>-</span><span> 11.92 mg/kg) > Zn (5.30 </span><span>-</span><span> 10.09 mg/kg) > (0.12 </span><span>-</span><span> 0.23 mg/kg) for Pb. The concentration of Cd, Cu and Co in ginger samples were below the limit of detection. The results revealed that ginger has the ability to accumulate relatively higher amounts of K and Mg among the determined essential metals. The soil samples have been found to be acidic pH, sandy clay loam in texture, a very low electrical conductivity and moderate level of (CEC, organic carbon, available phosphorus and total nitrogen). Although, a positive correlation between the levels of K, Mg, Zn, Mn in ginger and soil samples were observed. All the non-essential metals analyzed in this study were below the permissible ranges set by FAO/WHO.</span>展开更多
The use of cyanidin as a metallochromic agent in analyses of heavy metal is reported. Cyanidin is a ligand that was extracted from Gmelina arborea fruit and characterized. The cyanidin was used to form complexes with ...The use of cyanidin as a metallochromic agent in analyses of heavy metal is reported. Cyanidin is a ligand that was extracted from Gmelina arborea fruit and characterized. The cyanidin was used to form complexes with metals in five fish samples for the quantitative determination of Cu, Zn, Ca and Mg. The optimum pH for absorbances of the cyanidin-metal complexes was observed at 5. Experimental results obtained using cyanidin were compared with analyses results obtained by Atomic absorption spectrophotometry (AAS) and both methods were evaluated using paired T-test to ascertain the suitability of cyanidin as metallochromic agent for the quantitative determination of heavy metals in fish samples. A null hypothesis that cyanidin method is a good alternative to AAS was accepted for the analyses of Cu and Zn (p > 0.05). The paired T-test, however rejected the null hypothesis for the determination of Ca and Mg (p < 0.05). This study has provided a cheap, sensitive, rapid, simple and easy method for metal determination in analytical samples.展开更多
基金supported by Guizhou Provincial Science and Technology Foundation (Qian Sci.Co.ZK[2021] No.198)Doctoral Research Startup Project in 2017 of Guizhou Normal University in China+1 种基金the B-type Strategic Priority Program of the Chinese Academy of Sciences (Grant No.XDB41000000)the National Natural Science Foundation of China (41872046,41173074 and 42063008)。
文摘While engineered nanoparticles are widely used and maybe eventually released into the environment,natural nanoparticles are also commonly found in the Earth system.Nanoparticles may critically affect the geochemical migration of associated elements and pose potential threats to the ecological environment.It is necessary to establish an accurate and reliable method for measuring the concentration of nanoparticles.AAS is one of the most commonly used methods for the concentration determination of nanoparticles.However,till now,there has been no systematic report on how experimental variables affect AAS measurements.In this study,we used gold nanoparticles(AuNPs) as an example and studied the influences of a list of factors on the concentration determination of AuNPs by AAS,including digestion method,ionization interference,acidic medium,background correction method,and organic matter.We demonstrate that all these factors may have varying degrees of influence on the measured gold concentrations.When the gold colloid is digested at room temperature for more than 8 h or at 60℃ for more than 2 h,and the system contains a low concentration of organic matter,AAS can accurately measure the AuNP concentration at ppm-level.The deuterium lamp background deduction method is not recommended to use for samples with lower gold concentrations.
文摘Ginger (<i><span>Zingiber officinale</span></i><span>) is an important spice and medicinal plant used in different parts of the world. The objective of current study was to determine the level of essential and non-essential metals in ginger and its correlation with concentration of metals in the supporting soil. The level of K, Na, Ca, Mg, Mn, Fe, Zn, Cu, Co, Cd and Pb in soil and ginger cultivated in the selected districts of Wolaita zone, Southern Ethiopia were determined using flame atomic absorption spectrometry. A 0.5 g ginger sample was digested using a mixture of 4 ml HNO</span><sub><span style="vertical-align:sub;">3</span></sub><span> and 1.5 ml HClO</span><sub><span style="vertical-align:sub;">4</span></sub><span> at 210°</span><span>C</span><span> for 150 min</span><span>utes, and a 0.5 g soil sample was digested employing a mixture of 6 ml aqua-regia and 1 ml H</span><sub><span style="vertical-align:sub;">2</span></sub><span>O</span><sub><span style="vertical-align:sub;">2</span></sub><span> at 280°</span><span>C</span><span> for 150 minutes. The metal</span><span> concentrations range in dry weight basis for ginger samples is decreasing in the order: K (1691 </span><span>-</span><span> 3487 mg/kg) > Mg (701 </span><span>-</span><span> 1583 mg/kg) > Ca (862 </span><span>-</span><span> 1476 mg/kg) > Na (398 </span><span>-</span><span> 776 mg/kg) > Mn (325 </span><span>-</span><span> 672 mg/kg) > Fe (6.14 </span><span>-</span><span> 11.92 mg/kg) > Zn (5.30 </span><span>-</span><span> 10.09 mg/kg) > (0.12 </span><span>-</span><span> 0.23 mg/kg) for Pb. The concentration of Cd, Cu and Co in ginger samples were below the limit of detection. The results revealed that ginger has the ability to accumulate relatively higher amounts of K and Mg among the determined essential metals. The soil samples have been found to be acidic pH, sandy clay loam in texture, a very low electrical conductivity and moderate level of (CEC, organic carbon, available phosphorus and total nitrogen). Although, a positive correlation between the levels of K, Mg, Zn, Mn in ginger and soil samples were observed. All the non-essential metals analyzed in this study were below the permissible ranges set by FAO/WHO.</span>
文摘The use of cyanidin as a metallochromic agent in analyses of heavy metal is reported. Cyanidin is a ligand that was extracted from Gmelina arborea fruit and characterized. The cyanidin was used to form complexes with metals in five fish samples for the quantitative determination of Cu, Zn, Ca and Mg. The optimum pH for absorbances of the cyanidin-metal complexes was observed at 5. Experimental results obtained using cyanidin were compared with analyses results obtained by Atomic absorption spectrophotometry (AAS) and both methods were evaluated using paired T-test to ascertain the suitability of cyanidin as metallochromic agent for the quantitative determination of heavy metals in fish samples. A null hypothesis that cyanidin method is a good alternative to AAS was accepted for the analyses of Cu and Zn (p > 0.05). The paired T-test, however rejected the null hypothesis for the determination of Ca and Mg (p < 0.05). This study has provided a cheap, sensitive, rapid, simple and easy method for metal determination in analytical samples.
