ABSTRACT
OBJECTIVE: To establish a methodology for determining indium in human whole blood,serum and urine by inductively coupled plasma-mass spectrometry( ICP-MS). METHODS: The whole blood,serum and urine samples were diluted 10 times in 0. 01%( mass fraction) Triton X-100 plus 0. 50%( mass fraction) nitric acid solution,and the indium level was determined by ICP-MS. Rhodium standard solution was used as the internal standard control. RESULTS: The working curve obtained from measurement of whole blood,serum and urine of normal individuals was compared to the standard curve and showed no significant difference in quantitative analysis( P > 0. 05). The linearity range of indium concentration in whole blood,serum and urine was 0. 000-20. 000 μg / L,and all the correlation coefficients were greater than 0. 999 with a detection limit of 0. 144 μg / L. The recovery rates of whole blood,serum and urine were 87. 90%-95. 92%,91. 50%-94. 20% and 90. 40%-96. 57%,respectively. The relative standard deviations( RSDs) of within-run precision were 3. 81%-7. 05%,3. 75%-5. 90% and 4. 31%-6. 62%,respectively. The RSDs of between-run precision were 2. 90%-7. 10%,3. 80%-5. 92% and 4. 16%-5. 94%,respectively. Samples could be stored for at least 14 days under the temperature of- 20 ℃. The indium in whole blood,serum and urine of workers occupationally exposed to indium( exposure group,135 person-time) and control group workers( 120 person-time) were examined. Indium was detected for 17 person-time in whole blood and serum in the exposure group with a detection rate of 1. 26%. Indium was not detected in urine samples in exposure group. It was not detected in all samples in control group. CONCLUSION: This methodology has features of simple operation,high accuracy and good precision,which is suitable for the accurate quantitative analysis of indium in biological samples.
ABSTRACT
OBJECTIVE: To explore an improved method for determination of cyclohexane and methylcyclohexane in workplace air by solvent desorption-gas chromatography. METHODS: Cyclohexane and methylcyclohexane in workplace air were collected by activated carbon tubes,desorbed with carbon disulfide,separated by DB-1 capillary chromatography column,detected by flame ionization detector and quantified using the standard calibration curves. RESULTS: The linear range of the concentration of cyclohexane and methylcyclohexane were 1. 0-1 402. 2 and 0. 8-1 999. 4 mg / L respectively.Both the correlation coefficients were 0. 999 9. Both the detection limits were 0. 3 mg / L. The limits of quantification were1. 0 and 0. 8 mg / L respectively. Both the minimum detectable concentrations were 0. 2 mg / m3. The minimum quantitative mass concentrations of cyclohexane and methylcyclohexane were 0. 7 and 0. 6 mg / m3respectively( sample volume was 1. 5L). The average desorption efficiencies were 98. 5%-99. 3% and 97. 6%-99. 0% respectively. The relative standard deviations( RSD) of within-run precision were 0. 36%-0. 59% and 0. 34%-0. 50% respectively. The RSD of between-run precision were 0. 89%-2. 04% and 0. 87%-2. 22% respectively. The samples could be stored for up to 7 days at room temperature. CONCLUSION: This method has features of simple operation,high sensitivity and good precision,which is suitable for simultaneous determination of cyclohexane and methylcyclohexane in workplace air.