Preparation of Quantum Dots for Highly Sensitive Analysis of Alkali Metal and Ammonium Ions

• KITAGAWA Fumihiko

  Department of Frontier Materials Chemistry, Graduate School of Science and Technology, Hirosaki University

• KAI Minako

  Department of Material Chemistry, Graduate School of Engineering, Kyoto University

• OTSUKA Koji

  Department of Material Chemistry, Graduate School of Engineering, Kyoto University

Bibliographic Information

Other Title

• アルカリ金属イオン及びアンモニウムイオンの蛍光センシングのための量子ドットの作製
• アルカリ キンゾク イオン オヨビ アンモニウムイオン ノ ケイコウ センシング ノ タメ ノ リョウシ ドット ノ サクセイ

Abstract

A highly sensitive and selective analysis of alkali metal and ammonium ions was investigated on the basis of a Förster-type excitation energy transfer between two quantum dots (QDs) with different sizes. QDs are semiconductor nanoparticles and their emission wavelengths depend on their sizes. For the molecular recognition of potassium ion, mercaptoalkanoic 15-crown-5 ether was introduced onto the surface of QDs with their diameter of 2.1 (15C5-QDs2.1) and 2.6 nm (15C5-QDs2.6). When K⁺ is added to a mixed suspension of 15C5-QDs2.1 and 15C5-QDs2.6, the efficiency of the excitation energy transfer will be enhanced since the recognition of K⁺ brings a 1:2 sandwich-type complexation between the different size of QDs. As the concentration of K⁺ was increased, actually, the fluorescence intensity at longer wavelength derived from 15C5-QDs2.6 was increased. Thus, the signal transduction can be accomplished through the energy transfer resulting in a ratiometric change in the emission intensity. The limit of detection (LOD) of K⁺ was evaluated to be 0.50 μM, so that the sensitive detection of K⁺ was successful. When Na⁺ was added to the mixed suspension, the change in the fluorescence spectrum was not observed. Therefore, it was found that 15C5-QDs was K⁺ selective fluorescent probe. We also prepared Na⁺ or NH₄⁺ selective QDs probes by inducing mercaptoalkanoic 12-crown-4 ether or 18-crown-6 ether on QDs, respectively. The obtained LODs for Na⁺ and NH₄⁺ were 1.3 μM and 0.31 μM, respectively.

Journal

• BUNSEKI KAGAKU

  BUNSEKI KAGAKU 63 (12), 943-949, 2014

  The Japan Society for Analytical Chemistry

Keywords

• crown ether
• quantum dots
• energy transfer
• alkali metal ions
• fluorescence

Details

• CRID: 1390001204661503104
• NII Article ID: 130004732518
• NII Book ID: AN00222633
• DOI: 10.2116/bunsekikagaku.63.943
• NDL BIB ID: 025977013
• ISSN: 05251931
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I025977013
• Web Site: https://www.jstage.jst.go.jp/article/bunsekikagaku/63/12/63_943/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed