An alternative spectrophotometric method has been developed for total iron determination using flow injection analysis (FIA). The procedure is based on the coordination reaction between hydralazine and Fe2+ ions, whic...An alternative spectrophotometric method has been developed for total iron determination using flow injection analysis (FIA). The procedure is based on the coordination reaction between hydralazine and Fe2+ ions, which results in the formation of a purple complex monitored at 538 nm. For determination of total iron, Fe3+ ions were reduced using ascorbic acid. Under optimized conditions, a linear calibration graph (0.1 - 6.0 ?g?ml–1;n = 6) was obtained. The method allows LOD (3? of blank/slope = 0.06 ?g?ml–1) and LOQ (10? of blank/slope = 0.22 ?g?ml–1). The RSD ((s/ ) × 100) for a mixed standard containing 0.60 ?g?ml–1 Fe2+ and Fe3+ was 0.10% (n = 10). Recoveries of spiked samples were 94.3% - 106.0%. The analytical frequency was 60 h–1. The effect of possible interferences has been studied. The procedure was successfully applied for analysis of environmental samples. The real samples results were comparable with those obtained by the official method considering a paired t-test and 95% of confidence level.展开更多
The occurrence of extreme rainfall events and associated flooding has been enhanced due to climate changes, and is thought to influence the flux of total dissolved iron(TDI) in rivers considerably. Since TDI is a co...The occurrence of extreme rainfall events and associated flooding has been enhanced due to climate changes, and is thought to influence the flux of total dissolved iron(TDI) in rivers considerably. Since TDI is a controlling factor in primary productivity in marine ecosystems, alteration of riverine TDI input to the ocean may lead to climate change via its effect on biological productivity. During an extreme rainfall event that arose in northeastern China in 2013, water samples were collected in the midstream of the Heilongjiang River to analyze the concentration and species of TDI as well as other basic parameters. The speciation of TDI was surveyed by filtration and ultrafiltration methods.Compared with data monitored from 2007 to 2012, the concentration of TDI increased significantly during this event, with an average concentration of 1.11 mg/L, and the estimated TDI flux reached 1.2 × 10^5 tons, equaling the average annual TDI flux level.Species analysis revealed that low-molecular-weight complexed iron was the dominant species, and the impulse of TDI flux could probably be attributed to the hydrological connection to riparian wetlands and iron-rich terrestrial runoff. Moreover, dissolved organic matter played a key role in the flux, species and bioavailability of TDI. In addition,there is a possibility that the rising TDI flux could further influence the transport and cycling of nutrients and related ecological processes in the river, estuary coupled with the coastal ecosystems, which merits closer attention in the future.展开更多
Background: Anemia is one of the complications of chronic kidney disease (CKD) which necessitates multiple blood transfusions. These multiple transfusions are usually accompanied by Iron over load. The current study a...Background: Anemia is one of the complications of chronic kidney disease (CKD) which necessitates multiple blood transfusions. These multiple transfusions are usually accompanied by Iron over load. The current study aimed to assess the Iron profile in Sudanese patients with chronic renal failure received regular blood transfused. Materials and Methods: A descriptive analytical case control study was performed in Alturki Teaching Hospital, Khartoum, Sudan. A total of 90 Sudanese were enrolled in this study (30 CKD patients under hemodialysis and undergo multiple blood transfusion, 30 CKD patients under hemodialysis but not blood transfusion and 30 healthy controls, 51 (57%) were male and 39 (43%) were females, their age ranged between 28 to 75 years. Iron profile (serum iron, serum ferritin and total iron binding capacity (TIBC)) were measured using full automated Chemical analyzer Mindray BS 200 (China). Data were analyzed by using statistical package for social sciences (SPSS) verssion16. Results: The present study showed that serum iron and serum ferritin of those under hemodialysis and received regular blood transfusion patient were significantly higher compared to those under hemodialysis and did not received regular blood transfusion patients (P value 0.000 and 0.01) respectively. Conclusion: Patients with chronic renal failure and under hemodialysis and receive regular and multiple transfusions are prone to iron overload.展开更多
基金Financial support from CNPq,CNPq/CTHIDRO,CAPES and FAPEAL(Brazil)
文摘An alternative spectrophotometric method has been developed for total iron determination using flow injection analysis (FIA). The procedure is based on the coordination reaction between hydralazine and Fe2+ ions, which results in the formation of a purple complex monitored at 538 nm. For determination of total iron, Fe3+ ions were reduced using ascorbic acid. Under optimized conditions, a linear calibration graph (0.1 - 6.0 ?g?ml–1;n = 6) was obtained. The method allows LOD (3? of blank/slope = 0.06 ?g?ml–1) and LOQ (10? of blank/slope = 0.22 ?g?ml–1). The RSD ((s/ ) × 100) for a mixed standard containing 0.60 ?g?ml–1 Fe2+ and Fe3+ was 0.10% (n = 10). Recoveries of spiked samples were 94.3% - 106.0%. The analytical frequency was 60 h–1. The effect of possible interferences has been studied. The procedure was successfully applied for analysis of environmental samples. The real samples results were comparable with those obtained by the official method considering a paired t-test and 95% of confidence level.
基金supported by the National Nature Science Foundation of China (No. 41271499)the Major Science and Technology Program for Water Pollution Control and Treatment (No. 2012ZX07201004)
文摘The occurrence of extreme rainfall events and associated flooding has been enhanced due to climate changes, and is thought to influence the flux of total dissolved iron(TDI) in rivers considerably. Since TDI is a controlling factor in primary productivity in marine ecosystems, alteration of riverine TDI input to the ocean may lead to climate change via its effect on biological productivity. During an extreme rainfall event that arose in northeastern China in 2013, water samples were collected in the midstream of the Heilongjiang River to analyze the concentration and species of TDI as well as other basic parameters. The speciation of TDI was surveyed by filtration and ultrafiltration methods.Compared with data monitored from 2007 to 2012, the concentration of TDI increased significantly during this event, with an average concentration of 1.11 mg/L, and the estimated TDI flux reached 1.2 × 10^5 tons, equaling the average annual TDI flux level.Species analysis revealed that low-molecular-weight complexed iron was the dominant species, and the impulse of TDI flux could probably be attributed to the hydrological connection to riparian wetlands and iron-rich terrestrial runoff. Moreover, dissolved organic matter played a key role in the flux, species and bioavailability of TDI. In addition,there is a possibility that the rising TDI flux could further influence the transport and cycling of nutrients and related ecological processes in the river, estuary coupled with the coastal ecosystems, which merits closer attention in the future.
文摘Background: Anemia is one of the complications of chronic kidney disease (CKD) which necessitates multiple blood transfusions. These multiple transfusions are usually accompanied by Iron over load. The current study aimed to assess the Iron profile in Sudanese patients with chronic renal failure received regular blood transfused. Materials and Methods: A descriptive analytical case control study was performed in Alturki Teaching Hospital, Khartoum, Sudan. A total of 90 Sudanese were enrolled in this study (30 CKD patients under hemodialysis and undergo multiple blood transfusion, 30 CKD patients under hemodialysis but not blood transfusion and 30 healthy controls, 51 (57%) were male and 39 (43%) were females, their age ranged between 28 to 75 years. Iron profile (serum iron, serum ferritin and total iron binding capacity (TIBC)) were measured using full automated Chemical analyzer Mindray BS 200 (China). Data were analyzed by using statistical package for social sciences (SPSS) verssion16. Results: The present study showed that serum iron and serum ferritin of those under hemodialysis and received regular blood transfusion patient were significantly higher compared to those under hemodialysis and did not received regular blood transfusion patients (P value 0.000 and 0.01) respectively. Conclusion: Patients with chronic renal failure and under hemodialysis and receive regular and multiple transfusions are prone to iron overload.