Evaluation On The Iron Absorption And Utilization For Children

Objectives1The synthesis of57FeSO4solution as a stable isotopic tracer and establishing the method of isotopic detection.(1) To establish a method by using pure57Fe to synthesis57FeSO4in own laboratory, in order to provide a basis for follow-up study.(2) To establish a reliable and stable method to detect the isotopic ratio of iron by using multicollector inductively coupled plasma mass(MC-ICP-MS).2Evaluation on iron apparent absorption rate for children.(1) To evaluate the iron apparent absorption rate by fecal motoring with iron stable isotope tracer, and compare the differences between males and females.(2) To evaluate the iron apparent absorption rate by metabolic balance method.(3) To investigate the correlation between isotope trace and rare earth elements.3Evaluation on iron utilization and erythrocyte incorporation for children by stable isotopic tracer.(1) To evaluate the utilization of iron in whole blood at14days, and investigate the differences of utilization between males and females.(2) To evaluate the incorporation of iron in RBC at14days according to utilization, and compare the differences of incorporation between males and females.(3) To investigate the changes of57Fe in whole blood and RBC in order to provide data basis for physical requirements.(4) To compare the results of blood volume calculated by two methods, in order to obtain the appropriate calculation method. Methods1The synthesis of57FeSO4solution as a stable isotopic tracer and establishing the method of isotopic detection.1.1The synthesis of57FeSO4solution as a stable isotopic tracer.The pure stable isotope57Fe, which was enriched for94.693%, and dilute sulfuric acid were used for synthesis the57FeSO4, using Fe+H2SO4â†'FeSO4+H2↑as basic principle.56Fe was used for simulation test, appropriate amount of sulfuric were calculated by the stability, recovery and pH value of the solution. DyCl3and VC were add into solution after concentration, recovery and pH test.1.2Study on the analyses of IR for57Fe and spectrum for Dy with ICP-MS.Considering the concentrations of iron in biological samples collected from the human trial, the standard solution were prepared, and the iron in solution were separate by AGMP-1anion exchange resin, and the solution were tested by ICP-QMS in order to separate iron from other elements; The operating parameters were adjusted to the best state before test, and results were corrected by IRMM014. The single element solution, mixed elements standards and bio-samples with100μg/L iron were used to optimum working condition and analyze the IR.2Evaluation on iron apparent absorption rate for children.60students with aged10to12in Huaibei school were selected for body trial for14days, all the subjects were fasted for at least12h, they were orally administrated3mg stable iron tracer and0.3mg dy for10times in five days, the solution were given30min before breakfast and supper, and2carmine captures for each time were given in day1and day11before meal, all the fecal with SI and dy were selected in trial. The fecal samples were freeze dried, smashed and digested by microwave, then the solution were tested by AAS, ICP-QMS and MC-ICP-MS to got data of concentration of iron and dy, and also IR of57Fe/56Fe. The FAA were calculated by fecal motoring and corrected by recovery of Dy. 3Evaluation on iron utilization and erythrocyte incorporation for children by stable isotopic tracer.The whole blood and RBC samples were collected of male and female subjects after given stable iron14days, all the samples were digested by microwave and the solution were tested by AAS, MC-ICP-MS to got data of iron concentration and IR of57Fe/56Fe. Blood volume were calculated by body weight and total body water that tested by body composition analyzer, and the results of two methods were compared. Iron concentration in whole blood and RBC samples, IR of57Fe/56Fe and blood volume were used to calculate and compare the whole blood utilization of iron and erythrocyte incorporation at14days for different gender. The IR of57Fe/56Fe within90days were analyzed to investigate the abundance changes of57Fe in samples.Results1The synthesis of57FeSO4solution as a stable isotopic tracer and establishing the method of isotopic detection.1.1The synthesis of57FeSO4solution as a stable isotopic tracer.The solution were tested for6times, its concentrations and recoveries were2.68±0.12mg/mL and96.60±1.48%respectively. Solution were stable in3days and its RSD%were less than8%, and can be used as oral solution for the follow-up study since its microbial indicators qualified.1.2Study on the analyses of IR for57Fe and spectrum for Dy with ICP-MS.The recovery of100μg/L iron standard and blood standard solution were102%and106.49%respectively. The long-time and short-time RSD%of57Fe/56Fe IR were0.18%and0.26%, its stability and precision suit requirement or test. Recovery of dy in samples and standard solution were all more than98%.2Evaluation on iron apparent absorption rate for children.After12day fecal monitoring, the FAA of iron in different gender were26.71±2.94%and29.76±2.20%tested by FM, the FAA of females was significantly higher than that of males(P<0.05), the recoveries of dy were93.91±8.44%and94.24±6.98%respectively, and the FAA corrected by recovery of REEs were27.45±2.83%and31.01±2.48%(P＜0.05); FAA of different gender calculated by MB were8.05±0.90%and9.13±0.57%Good linear regression was observed for the excretions of isotopic tracer and REEs(r=0.745, P＜0.01). There was a similar trends of57Fe/56Fe IR, only the trend rise and fall was little slowly in females.3Evaluation on iron utilization and erythrocyte incorporation for children.According to BV calculated by weight, the whole blood utilization of iron at14days of different gender were20.4±2.0%and22.0±0.8%, the erythrocyte incorporation were88.66±2.93%and93.89±2.27%. And according to BV calculated by TBW, the whole blood utilization of iron at14days of different gender were20.4±2.0%and22.0±0.8%, the erythrocyte incorporation were88.66±2.93%and93.89±2.27%, the utilization and incorporation of females were all significantly higher than that of males(P<0.05); The blood volumes calculated by body weight and total body water were3.19±0.41L and3.31±0.34L for males,3.15±0.29L and3.13±0.20L for females, there was no significantly difference between two methods(P>0.05). IR of57Fe/56Fe in whole blood samples were increased rapidly within28days and then declined slowly, but IR in RBC samples were declined after90days.Conclusion1The synthesis of57FeSO4solution as a stable isotopic tracer and establishing the method of isotopic detection.1.1The synthesis of57FeSO4solution as a stable isotopic tracer.The method using pure stable iron as raw material to synthesis57FeSO4for body trail in laboratory was reliable, simple and high recovery, and deserve to promotion.1.2Study on the analyses of IR for57Fe and spectrum for Dy with ICP-MS.(1) The methods of MC-ICP-MS and ICP-QMS can wonderfully eliminate the impact of various sources of interference on the data. (2) The method of IR analysis for57Fe/56Fe by MC-ICP-MS in bio-samples has a good stability and precision.(3) The method of dy concentration by ICP-QMS in fecal samples has a higher stability and recovery.2Evaluation on iron apparent absorption rate for children.(1) The REEs has a similar gastrointestinal transit process with stable iron tracers, its recovery can be used to correct the absorption of iron. Dy has a good recovery in this study with95%-105%.(2) Both male and female have a higher absorption rate of iron by given stable isotope with empty stomach. The absorption of female is significantly higher than that of males.(3) The FAA calculated by MB of different gender were all less than10%, and FAA of male were more less(P<0.05).3Evaluation on iron utilization and erythrocyte incorporation for children by stable isotopic tracer.(1) The method to analyze the whole blood utilization and erythrocyte incorporation is feasible and reliable, which given large dose of stable iron tracer by orally administration with empty stomach, it can provide a data basic for physical requirement calculation.(2) The whole blood utilization of iron and the erythrocyte incorporation of females are all significantly higher than that of males.(3) IR of S7Fe/56Fe in whole blood samples were increased rapidly within28days and then declined slowly, but IR in RBC samples were declined after90days.(4) Both utilization and erythrocyte incorporation have a relationship with body iron status, and have a negative correlation with serum ferritin.(5) The blood volume results calculated by two methods are similar, but the result according to TBW arc suitable for populations with different body composition.