RESUMEN
OBJECTIVE: To establish a detection method for 1-bromopropane in human urine by headspace gas chromatography-mass spectrometry( GC-MS). METHODS: A 4. 00 m L portion of the urine sample was placed in a 15. 00 m L headspace vial and 20. 00 μL of 1-bromobutane internal standard solution( 204. 200 mg / L mass concentration) was added.The bottle cap was immediately sealed. The sample was heated to 80 ℃ with an equilibrium time of 20 minutes in the headspace device. The vapor in the headspace vial was separated by GSBP-FFAP( 30. 00 m × 0. 25 mm × 0. 25 μm)capillary chromatography column and the ion was used to carry out quantitative determination of 1-bromopropane in human urine. RESULTS: The good linearity range of 1-bromopropan mass concentration was 0. 025-1. 012 mg / L, and the correlation coefficient was 0. 999 8. The detection limit was 7. 5 μg / L( urine sample volume,4. 00 m L) and the limit of quantitation was 25. 0 μg / L( urine sample volume,4. 00 m L). The relative standard deviation( RSD) of within-run precision was 2. 61%-4. 08%,and the RSD of between-run precision was 2. 79%-6. 25%. The average recovery rate was99. 34%-105. 94%. CONCLUSION: The method of determining 1-bromopropane in human urine by headspace GC-MS has the features of high sensitivity,good linear relationship,low interference,good precision and easy operation,which is suitable for detecting 1-bromopropane mass concentration in human urine.
RESUMEN
In this study, zebrafish larvae are introduced as an in vivo platform to examine the neurotoxicity and developmental toxicity associated with continuous exposure to a concentration gradient of different sizes of SiO2 nanoparticles (15 nm and 50 nm diameter) to determine the dose effect and size effect of SiO2 nanoparticle (NP)-induced toxicity. Bovine serum albumin (BSA-V) is utilized as a stabilizing agent to prevent coagulation of the SiO2 nanoparticles. To the best of our knowledge, this study is the first to describe locomotor activity assays linking rest/wake behavioral profiles for the purpose of investigating the neurotoxicity of NPs. In addition, developmental toxicological endpoints including mortality, LC50 , malformation, and cartilaginous deformity are assessed. The results show a concentration-dependent increase in behavioral neurotoxicity, mortality, and malformation among larvae treated with the SiO2 nanoparticles of 15 nm and 50 nm. A comparison of the 15 nm and 50 nm NPs by K-means clustering analysis demonstrates that the 15 nm NPs have a greater neurotoxic effect than the 50 nm NPs, with the 50 nm NPs exhibiting greater developmental toxicity on the zebrafish larvae than the 15 nm NPs.