ABSTRACT
OBJECTIVE:To establish a method for the contents determination of 5 heavy metals in Ershiwuwei shanhu pills, and to investigate the contents of heavy metals in Ershiwuwei shanhu pills produced by 5 manufacturers from different districts of Tibet. METHODS:Ershiwuwei shanhu pills were digested by HNO3-HClO4(4:1,V/V).The contents of 3 heavy metals as Cu,Pb, Cd in samples were measured by flame atomic absorption spectrometry(FAAS). The contents of 2 heavy metals as As,Hg in samples were measured by hydride generation atomic absorption spectrometry(HG-AAS). RESULTS:5 kinds of heavy metals have good linear relationship in the corresponding mass concentration range(all r≥0.999 1). The limits of detection of Cu,Pb, Cd were 0.001 6,0.041 2,0.036 3 mg/L,and the limits of quantitation were 0.005 3,0.137 3,0.121 0 mg/L;the limits of detection of As,Hg were 0.325 7,0.692 3 μg/L,and the limits of quantitation were 1.085 7,2.307 7 μg/L. RSDs of precision tests were ≤5.54%(n=6);RSDs of stability tests were all≤3.79%;RSDs of reproducibility tests were ≤3.72%. The average recovery rates were 91.34%-110.11%(RSDs were 0.66%-6.80%,n=6). Results of contents determination showed that the contents of Cu in samples from 5 manufacturers were not out of limits,but the contents of Cd and Hg were all out of limits; the contents of Pb in samples from 4 manufacturers were out of limits,and the contents of As in samples from 2 manufacturers were out of limits. CONCLUSIONS:The established method has good accuracy,sensitivity,stability and reproducibility,and it is suitable for contents determination of 5 heavy metals in Ershiwuwei shanhu pills. To some extent,there is a problem of excessive heavy metals in samples from 5 manufacturers.
ABSTRACT
Objective To evaluate the method for detection of urinary mercury using a Zeeman atomic absorption mercury analyzer and to provide a reference for selecting a convenient method for mercury detection in experiments and clinical diagnoses. Methods Urinary mercury was detected by Zeeman atomic absorption spectroscopy (ZAAS) and hydride generation atomic absorption spectrometry (HG-AAS), and the detection limit, accuracy, precision and consistency of the two methods were compared. Results The Data collected by ZAAS and HG-AAS showed a good linear relationship in the range of 0 -1000 ng/mL (ZASS, R2 =1. 0000) and 0 -20 ng/mL (HG-AAS, R2 =0. 9990). The detection limits of ZAAS was 0. 156 ng/mL and that of HG-AAS was 1. 593 ng/mL, indicating that ZAAS is more sensitive. The recovery rate of standard addition of ZAAS was between 97. 5％ and 103. 2％, and that of HG-AAS was between 95. 6％ and 104. 5％. After measurement of 10 ng/mL and 100 ng/mL mercury standard solutions repeated for 10 times, the relative standard deviation (RSD) of ZAAS was 0. 30％ and 0. 36％ respectively, and the RSD of HG-AAS was 2. 82％ and 1. 11％, respectively. The accuracy and precision of both the two method met the standards of GBZ/T 210. 5-2008, and the precision of ZAAS was better. A total of 30 urine samples were measured by these two methods. The results were compared with paired-samples t-test and showed a non-significant difference (P ＞ 0. 05), indicating a high consistency of these two method (R2 =0. 9961). Conclusions ZAAS is a convenient and accurate method for the detection of urinary mercury, with a relatively low detection limit and better precision.
ABSTRACT
Objective To investigate the present status of Chinese patent medicine with realgar (As2S2) and to research arsenic dissolution in different pH values. Methods Data on the amount of Chinese patent medicine with realgar, the content of realgar, the method of taking medicine and so on were collected from the Chinese traditional medicine protection and criterions issued by the Chinese Ministry of Health in 2005, and evaluated the using status of Chinese patent medicine with realgar. The realgar powder was dissolved in solutions at different pH values (1, 3, 5, 7, 9, 11) in 37℃ water for 4 h, respectively, then arsenic was determined with cold trap hydride generation atomic absorption spectrometry to calculate the amount of dissolved arsenic. Results One hundred and twenty-one (3.13%) realgar medicaments were recorded in a total of 3 860 various Chinese patent medicaments, including 74 medicaments with both realgar and cinnabar (HgS) . Of all medicaments with realgar, 97 medicaments (80.17%) were for oral application, 10 medicaments (8.26%) were for external application, and 14 medicaments (11.57%) were for both oral and external application. 45 medicaments with realgar (1.17%) could be used in children; 108 medicaments with realgar (89.26%) contained arsenic 15%; The relative amount of arsenic in medicaments with realgar was from 0.46% to 27.52%. Daily intake of arsenic was 500 mg for 11 medicaments (9.09%). Only inorganic arsenic (iAs) was detected when 1 mg realgar was dissolved in solution with pH values of 1, 3, 5, 7, 9, 11. The levels of dissolved iAs seemed increased with the pH values, which were 1.58 ?g, 1.24 ?g, 1.57 ?g, 1.62 ?g, 2.28 ?g and 4.76 ?g, respectively. Conclusion Considering the common use of realgar in Chinese patent medicine and the high level of arsenic in realgar, the potential danger can not be ignored. It is possible that arsenic in realgar may be much easier to be absorbed in intestine than in stomach.
ABSTRACT
OBJECTIVE: To establish a method for the determination of the content of thiomersal in hepatitis B vaccine. METHODS: The content of thiomersal in hepatitis B vaccine was determined by flow injection-hydride generation atomic absorption spectrometry. The samples were treated by reflux digestion method with 4% sulphuric acid as medium,0.5% potassium borohydride as reducing agent,and 0.5% sulphuric acid as supporting liquid. RESULTS: The linear range of thiomersal was 5.0～100 ?g?L-1,with an average recovery rate of 100.6%(RSD=0.89%) and the lowest detection limit of 1.00 ?g?L-1. CONCLUSION: The method is simple,rapid and sensitive,and suitable for the determination of the content of thiomersal in hepatitis B vaccine.