检索结果-南通市图书馆

Determination of ammonium on an integrated microchip with LED-induced fluorescence detection

Journal of Environmental Sciences 2012年第3期24卷 564-570页

作者： Shuhua Xue Katsumi Uchiyama Hai-fang Li Department of Chemistry Tsinghua UniversityBeijing 100084China College of Chemistry and Chemical Engineering Fuzhou UniversityFuzhou 350108China Department of Applied Chemistry Graduate School of Urban Environmental SciencesTokyo Metropolitan UniversityMinamiohsawaHachiojiTokyo 192-0364Japan

A simply fabricated microfluidic device integrated with a fluorescence detection system has been developed for on-line determination of ammonium in aqueous samples. A 365-nm light-emitting diode （LED） as an excitation source and a minor band pass filter were mounted into a polydimethylsiloxane （PDMS）-based microchip for the purpose of miniaturization of the entire analytical system. The ammonium sample reacted with o-phthaldialdehyde （oPA） on-chip with sodium sulfite as reducing reagent to produce a fluorescent isoindole derivative, which can emit fluorescence signal at about 425 nm when excited at 365 nm. Effects of pH, flow rate of solutions, concentrations of oPA-reagent, phosphate and sulfite salt were investigated. The calibration curve of ammonium in the range of 0.018- 1.8 μg/mL showed a good linear relationship with R2 = 0.9985, and the detection limit was （S /N = 3） 3.6 × 10 4 μg/mL. The relative standard deviation was 2.8% （n = 11） by calculating at 0.18 μg/mL ammonium for repeated detection. The system was applied to determine the ammonium concentration in rain and river waters, even extent to other analytes fluorescence detection by the presented device.

关键词： microfluidic chip light emitting diode o-phthaldialdehyde fluorescence ammonium

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Improved speciation of dissolved organic nitrogen in natural waters: amide hydrolysis with fluorescence derivatization

引用

Journal of Environmental Sciences 2008年第10期20卷 1273-1280页

作者： Ryan L.Fimmen Tamara D.Trouts Daniel D.Richter Jr. Dharni Vasudevan School of Earth Sciences The Ohio State University 125 S.Oval MallColumbus OH 43210 USA.Nicholas School of the Environment and Earth Sciences Duke University Durham NC 27708 USA School of Earth Sciences The Ohio State University 125 S.Oval MallColumbus OH 43210 USA Nicholas School of the Environment and Earth Sciences Duke UniversityDurham NC 27708 USA. Nicholas School of the Environment and Earth Sciences Duke UniversityDurham NC 27708 USA.Department of Chemistry Bowdoin CollegeBrunswick ME 04011 USA

The objective of this study was to improve primary-amine nitrogen (1°-N) quantification in dissolved organic matter (DoM) originating from natural waters where inorganic forms of N, which may cause analytical interference, are commonly encountered. Efforts were targeted at elucidating organic-N structural criteria influencing the response of organic amines to known colorimetric and fluorescent reagents and exploring the use of divalent metal-assisted amide hydrolysis in combination with fluorescence analyse...

关键词： dissolved organic matter/nitrogen (DoM/DoN) o-phthaldialdehyde fluorescamine ninhydrin amino acids amide hydrolysis peptides

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：