摘要: |
海洋生态系统中, 羟胺作为多种微生物作用的中间产物, 在氮的海洋生物地球化学循环中起着重要作用。目前, 缺乏针对海洋中微量羟胺简便易行的测定方法。本研究借鉴海水中铁离子测定原理, 首次应用硫酸铁铵-邻菲罗啉法间接测定海水中微量羟胺浓度, 确定出该方法可在30—120min内稳定、快速地测定微量羟胺。通过对方法不确定度的系统评价得出, 此方法灵敏度高、响应快、稳定性和重复性好, 操作简便, 适于羟胺检测浓度范围为0.020—0.800 mg/L (R2=0.9996, P<0.0001, n =32); 天然海水中平均加标回收率达到106.9% (RSD=1.71%)。检测室内处于培养指数增长期的东海原甲藻(Prorocentrum donghaiense)藻液发现, 羟胺主要被合成于藻细胞内部, 其胞外含量低至检测下限附近。 |
关键词: 羟胺 分光光度法 氮 邻菲罗啉 |
DOI:10.11693/hyhz20131100188 |
分类号:P734.4 |
基金项目:国家自然科学基金资助项目, 41276115 号; 国家重点基础研究发展计划(973 项目), 2010CB428706 号; 国家基金委创新研究群体项目, 41121064 号。 |
|
INDIRECT DETERMINATION OF HYDROXYLAMINE IN SEAWATER IN SPECTROPHOTOMETRY |
Lu Guangyuan,Song Xiu-xian and Yu Zhi-ming
|
Institute of Oceanology, Chinese Academy of Sciences,Institute of Oceanology, Chinese Academy of Sciences,Institute of Oceanology, Chinese Academy of Sciences
|
Abstract: |
Nitrogen compounds in seawater are altered by microbial enzymes activities in many biogeochemical processes. However, no enough attention has been paid to minor or trace quantity of hydroxylamine in seawater, and no direct determination of hydroxylamine in seawater is available at present. We developed an indirect method to measure hydroxylamine in seawater according to the traditional measurements applied in soil and wastewater in industry. In this method, hydroxylamine is reduced from Fe3+ to Fe2+ under acidic condition, and then the Fe2+ ion is coordinated with 1, 10-phenanthroline. Being well shaken and mixed, the solution would turn orange in color and an adsorption peak would be shown at wavelength 510 nm, at which difference from the background can be measured to calculate hydroxylamine concentration. The method has been proven quick and accurate in high precision, and the correlation is significant in range of 0.02—0.8 mg/L (R2=0.9996, P<0.0001, n=32). The recovery rate of 0.20, 1.00, 2.00μg hydroxylamine added into 2.5 mL seawater reached 105.9%, 108.1%, 106.8%, respectively. We took Prorocentrum donghaiense cells as a case study, from which we found that hydroxylamine compound is synthesized mainly in the intracellular endoplasm, not in extracellular culture. |
Key words: hydroxylamine spectrophotometry nitrogen 1, 10-phenanthroline |