[Application Value of Capillary Electrophoresis in Screeningß-Thalassemia of Children].

OBJECTIVE: to explore the value of capillary electrophoresis in screening ß- thalassemia of children, and to establish the cutoff values of HbA2 and HbF in our laboratory. METHODS: The data of hemoglobin capillary electrophoresis and genetic diagnosis of ß- thalassemia from 886 examined children were retrospectively analyzed. The cutoff values of HbA2 and HbF were determined by ROC curve. RESULTS: The cutoff value of HbA2 screening minor ß- thalassemia was 3.65%, the specificity was 0.996, and the sensitivity was 0.995. The cut-off value of HbF for screening minor ß- thalassemia was 1.45%, specificity was 0.751 and sensitivity was 0.675. Thus, 1 case with codon5 (CCT→C) mutation, 1 case with SEA -HPFH ß deletion, 1 case with - 28 (A→G) merger IVS-Ι-128 (T→G) double heterozygous mutations yet were found out, 1 case with 47 bp ß gene missing has not yet been reported in literature. CONCLUSION: Capillary electrophoresis has more high sensitivity and specificity in the screening of ß- thalassemia in children, especially for the detection of rare ß- thalassemia.

[Research on removal of copper, manganese and zinc ions using cation exchange membrane based on Donnan dialysis].

Based on Donnan dialysis technique, the mechanism that influences the exchange capacity of the membrane and the interaction mechanism between two co-existing ions are investigated in this paper, where the cation exchange membrane is applied to remove the heavy metal ions such as copper, manganese, zinc. The following results were obtained: It is applicable to use the cation exchange membrane to remove copper, manganese and zinc ions and 75%-85% of removal efficiency can be obtained; when the concentration and charge number are the same, the smaller the radius of hydrated heavy metal, the quicker the ion diffuse and consequently the higher removal efficiency the membrane can achieve, which is the main factor; when the radius of the hydrated heavy metals are approximately same, the membrane will have higher removal efficiency to the ion with lower atomic number; when the ions with same charge number and concentration co-exist, both of them are removed but with different removal speeds for existing of disturbance between them and there exist diffusion competition, i.e. those who are more prone to be exchanged will be more competitive and more likely to low the removal rate of the other ion seriously; if the total concentration of the ions is far lower than the exchange capacity of the membrane, the removal efficiency when the ions coexist is not lower too much than that of the case when they exist lonely.

Spatially resolved, laser-induced breakdown spectroscopy, development, and application for the analysis of Al and Si in nickel-based alloys.

Spatially resolved laser-induced breakdown spectroscopy (SRLIBS) was used for the characterization of aluminum and silicon in nickel-based alloys. The very low invasiveness of the technique was one of the figures of merit of LIBS; however, the relative complexity of the instrument often hindered the widely acceptance of LIBS. Spatially resolved LIBS could provide accuracy and precision comparable to those obtained with temporally resolved LIBS (TRLIBS). In the nongated spatially resolved LIBS, the maximum atomic emission could be obtained with relative low continuum background emission at optimum observation spatial position. The study was done with a Nd:YAG laser at 532 nm, 3.0 mJ laser energy, and 0.2 mbar in argon. The experimental results obtained under optimum conditions were compared to those obtained with TRLIBS. SRLIBS gave reliable results without the tedious optimization of the delay time and gate width.