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Journal Articles

Purification of anionic fluorescent probes through precise fraction collection with a two-point detection system using multiple-stacking preparative capillary transient isotachophoresis

Haraga, Tomoko; Tsujimura, Hiroto*; Miyauchi, Saori*; Kamimura, Takuya*; Shibukawa, Masami*; Saito, Shingo*

Electrophoresis, 41(13-14), p.1152 - 1159, 2020/07

 Times Cited Count:3 Percentile:50.59(Biochemical Research Methods)

A novel combination of CE-based separation techniques was used for the precise fractionation of ionic compounds from impurities. The combination of on-capillary concentration and separation using transient isotachophoresis, with multiple injections and a two-point detection system provided higher efficiency, and accuracy at a microliter-scale injection volume, than when CE was individually used for purification. In this paper, we present successful applications of the CE fractionation techniques for the purification of fluorescein, fluorescein-4-isothiocyanate, two fluorescent metal ion probes, and a fluorescein-modified DNA aptamer. The purity of the isolated fluorescent probes ranged from 95 to 99%. The purified probe solutions were practical for use as purified stock solutions. The method developed was useful for the purification of anionic fluorescent reagents to be of ultratrace analytical grade for use with CE-LIF.

Journal Articles

Advanced gel electrophoresis techniques reveal heterogeneity of humic acids based on molecular weight distributions of kinetically inert Cu$$^{2+}$$-humate complexes

Marumo, Kazuki*; Matsumoto, Atsumasa*; Nakano, Sumika*; Shibukawa, Masami*; Saito, Takumi*; Haraga, Tomoko; Saito, Shingo*

Environmental Science & Technology, 53(24), p.14507 - 14515, 2019/12

 Times Cited Count:0 Percentile:0(Engineering, Environmental)

Humic acids (HA) are responsible for the fate of metal ions in the environment. We developed a polyacrylamide gel electrophoresis (PAGE) technique to investigate the MW distributions of metal ion (copper ion). Combining contaminant-metal-free and high-resolution PAGE systems for HA provided accurate MW distributions for the metal ions. Coupling this system with UV-Vis spectrometry and the excitation-emission matrix (EEM) spectrometry-parallel factor analysis (PARAFAC) method revealed new insights into metal-HA complex. Interestingly, the MW distributions of the three metal ions were entirely different, indicating that the presence of specific binding environments in HA for the metal ions depending its MW. The MW distributions of five fluorescent components were associated with the metal ion distributions. Our PAGE-based methodology suggests that metal binding sites and fluorescent components in HA exhibit heterogeneity in terms of metal binding affinity and MW.

Journal Articles

Safe and rapid development of capillary electrophoresis for ultratrace uranyl ions in radioactive samples by way of fluorescent probe selection for actinide ions from a chemical library

Haraga, Tomoko; Ouchi, Kazuki; Sato, Yoshiyuki; Hoshino, Hitoshi*; Tanana, Rei*; Fujihara, Takashi*; Kurokawa, Hideki*; Shibukawa, Masami*; Ishimori, Kenichiro; Kameo, Yutaka; et al.

Analytica Chimica Acta, 1032, p.188 - 196, 2018/11

 Times Cited Count:6 Percentile:33.4(Chemistry, Analytical)

The development of safe, rapid and highly sensitive analytical methods for radioactive samples, especially actinide (An) ions, represents an important challenge. Here we propose a methodology for selecting appropriate emissive probes for An ions with very low consumption and emission of radioactivity by capillary electrophoresis-laser-induced fluorescence detection (CE-LIF), using a small chemical library of probes with eight different chelating moieties. It was found that the emissive probe, which possesses the tetradentate chelating moiety, was suitable for detecting uranyl ions. The detection limit for the uranyl-probe complex using CE-LIF combined with dynamic ternary complexation and on-capillary concentration techniques was determined to be 0.7 ppt. This method was successfully applied to real radioactive liquid samples collected from nuclear facilities.

Journal Articles

Application of capillary electrophoresis with laser-induced fluorescence detection for the determination of trace neodymium in spent nuclear fuel using complexation with an emissive macrocyclic polyaminocarboxylate probe

Haraga, Tomoko; Saito, Shingo*; Sato, Yoshiyuki; Asai, Shiho; Hanzawa, Yukiko; Hoshino, Hitoshi*; Shibukawa, Masami*; Ishimori, Kenichiro; Takahashi, Kuniaki

Analytical Sciences, 30(7), p.773 - 776, 2014/07

 Times Cited Count:5 Percentile:21.87(Chemistry, Analytical)

A simple and rapid method with low radiation exposure risk was developed for the determination of neodymium in spent nuclear fuel by CE with LIF detection using a fluorescent ligand having a macrocyclic hexadentate polyaminocarboxylate structure. The concentration of Nd(III) in a spent nuclear fuel sample was determined with no interference from various matrix elements, including lanthanides and uranium (at a 200-fold excess), with 92 $$pm$$ 3% recovery. This is due to method's high resolution based on establishing a ternary complex equilibrium during migration in which the hydroxyl ion plays an auxiliary role.

Journal Articles

Highly sensitive detection of neodymium ion in small amount of spent nuclear fuel samples using novel fluorescent macrocyclic hexadentate polyaminocarboxylate probe in capillary electrophoresis-laser-induced fluorescence detection

Saito, Shingo*; Sato, Yoshiyuki*; Haraga, Tomoko; Nakano, Yuta*; Asai, Shiho; Kameo, Yutaka; Takahashi, Kuniaki; Shibukawa, Masami*

Journal of Chromatography A, 1232, p.152 - 157, 2012/04

 Times Cited Count:11 Percentile:41.46(Biochemical Research Methods)

A rapid and high-sensitive detection method of total concentration of Nd ion in a spent nuclear fuel sample is desirable since precise quantification of total Nd is useful as indicator of burnup. In this work, a capillary electrophoresis-laser-induced fluorescent detection method (CE-LIF) was proposed for analysis of total Nd in the spent fuel sample solution, employing a newly synthesized metal fluorescent probe with a fluorescein and a macrocylic hexadentate chelating group, FTC-ABNOTA, for lanthanide (Ln) ions. The mutual separation among the Ln-FTC-ABNOTA complexes was achieved by pH control providing dynamic ternary complexation with hydroxide ions. In this method, high resolution of Nd from other Ln ions with high resolution of 1.3-1.9 and a very low detection limit of 3.2 ppt were successfully obtained. A simulated spent fuel sample containing various metal ions was examined, so that a good quantification result with 99.3% recovery was obtained even with large excess of U.

Journal Articles

Capillary electrophoresis with laser-induced fluorescent detection method using highly emissive probes for analysis of actinides in radioactive wastes

Haraga, Tomoko; Nakano, Yuta*; Shibukawa, Masami*; Kameo, Yutaka; Takahashi, Kuniaki; Saito, Shingo*

Proceedings of 14th International Conference on Environmental Remediation and Radioactive Waste Management (ICEM 2011) (CD-ROM), p.1461 - 1465, 2011/09

Actinides are important nuclides for the analysis of radioactive wastes from nuclear fuel cycle facilities. In order to achieve simple and rapid analysis of actinides, capillary electrophoresis-laser-induced fluorescent detection method (CE-LIF) is one of the potential candidates. In this study, new emissive probes of actinide ions suitable for CE-LIF were developed for the first time. The detection and separation of americium and neptunium ions as model nuclides were examined using several new emissive complexing probes, each of which possessed a fluorophore and a different chelating moiety. Using acyclic and macrocyclic multidentate probes, the highly sensitive fluorescent detection of Am and Np was successfully achieved. The results suggests that the probe with an acyclic hexadentate chelating moiety is suitable for detection and separation of Am and Np. The detection limit of mid-ppt levels was determined.

Oral presentation

Separation and enrichment of rare-earth elements by high-speed countercurrent chromatography with an aqueous biphasic system

Shimizu, Kohei; Saito, Shingo*; Naganawa, Hirochika; Shibukawa, Masami*

no journal, , 

no abstracts in English

Oral presentation

Study on highly emissive probes with various chelating moieties for analysis of actinides by capillary electrophoresis with laser-induced fluorescent detection

Haraga, Tomoko; Nakano, Yuta*; Shibukawa, Masami*; Saito, Shingo*; Kameo, Yutaka; Takahashi, Kuniaki

no journal, , 

For the safe disposal of radioactive wastes, a simple and highly sensitive analytical method for actinides in waste samples is required. In this study, a capillary electrophoresis with laser induced fluorescent detection was examined for analysis of neptunium ($$^{237}$$Np) and americium ($$^{243}$$Am). Applying a pre-capillary complexation technique using several new emissive complexing probes with various chelating moieties, the highly sensitive fluorescent detection of Np and Am was succeeded. In addition, the separation of Np and Am was achieved for a multidentate probe. The detection limit was obtained at mid-ppt levels.

Oral presentation

Capillary electrophoresis with laser-induced fluorescent detection method using highly emissive probes for analysis of uranium in radioactive wastes

Haraga, Tomoko; Sato, Yoshiyuki*; Shibukawa, Masami*; Kameo, Yutaka; Takahashi, Kuniaki; Saito, Shingo*

no journal, , 

JP, 2012-034711   Patent publication (In Japanese)

Actinides (Th, U, Np, Pu, Am, Cm) are important nuclides for the analysis of radioactive wastes from nuclear facilities. In order to achieve simple and rapid analysis of actinides, capillary electrophoresis-laser-induced fluorescent detection method (CE-LIF) is one of the potential candidates. In this study, new emissive probes of uranium suitable for CE-LIF were developed. The detection and separation of uranyl ions were examined using several new emissive complexing probes, each of which possessed a fluorophore and a different chelating moiety. Using acyclic tetradentate probes, the highly sensitive fluorescent detection of uranyl ions was successfully achieved. The detection limit of mid-ppt levels was determined.

Oral presentation

Development of the fluorescent probe for capillary electrophoresis aiming at simple and safe analysis of actinide ions

Sato, Yoshiyuki; Saito, Shingo*; Haraga, Tomoko; Nakano, Yuta*; Kameo, Yutaka; Takahashi, Kuniaki; Shibukawa, Masami*

no journal, , 

In this research, capillary electrophoresis - laser induced fluorescence detecting method (CE-LIF) for the simple screening method of actinide (An) ions was studied. In order to detect An ion by CE-LIF, eight kinds of fluorescent probes were synthesized which have acyclic or macrocyclic 4-8 denate chelating group. An ions were derivatized to from a strongly fluorescent complexes with the probe to suppress the quenching of the ligand - centered emission. These An complexes were applied to CE-LIF, and it looked for the probe suitable for detection of An ions. As a result, Th, U and Np were detectable with octadenate probe, tetradenate probe and hexa and hepta probe respectively. Am was detectable with all the probes except tetradenate probe. An ions were separated from coexistence metal ions, such as Ca$$^{2+}$$, Fe$$^{3+}$$, Al$$^{3+}$$ and lanthanide ions, and a lower detection limits of tens ppt revel for An ions were successfully.

Oral presentation

Development of the novel fluorescent probe selective for uranyl ion for capillary electrophoresis-laser induced fluorescence detection

Sato, Yoshiyuki; Saito, Shingo*; Haraga, Tomoko; Ito, Yuki*; Kameo, Yutaka; Takahashi, Kuniaki; Shibukawa, Masami*

no journal, , 

JP, 2012-034711   Patent publication (In Japanese)

In this research, capillary electrophoresis-laser induced fluorescence detecting method (CE-LIF) as a simple and rapid analytical method for uranyl ion was studied. In order to detect uranyl ion by CE-LIF, the novel fluorescent probe whose chelating group was phenanthroline dicarboxylic acid, was synthesized. This planer tetradenate probe forms a stable complex with uranyl ion. And this complex had strong fluorescence to suppress the quenching of the ligand-centered emission. This complex was applied for CE-LIF and investigated in order to separate from other metal ions. As a result, uranyl ion formed an inert complex and was detected successfully. Furthermore an uranyl ion was separated from coexistence metal ions, such as Ca$$^{2+}$$, Fe$$^{3+}$$, Al$$^{3+}$$ and lanthanide ions, and a lower detection limit of tens ppt revel for uranyl ion was successfully.

Oral presentation

Capillary electrophoresis with laser-induced fluorescence detection for ultratrace uranyl ion using a highly emissive phenanthroline-dicarboxylate derivative probe

Haraga, Tomoko; Sato, Yoshiyuki; Ouchi, Kazuki*; Shibukawa, Masami*; Ishimori, Kenichiro; Kameo, Yutaka; Saito, Shingo*

no journal, , 

Uranium is an important nuclide for the analysis of radioactive wastes from nuclear fuel cycle facilities. In order to achieve simple and rapid analysis of uranium, capillary electrophoresis-laser-induced fluorescent detection method (CE-LIF) is one of the potential candidates. In this study, a highly emissive probe of uranyl ion suitable for CE-LIF was developed. The detection and separation of uranyl ion were examined using several new emissive complexing probes, each of which possessed a fluorophore and a different chelating moiety. Using a tetradentate probe, phenanthroline dicarboxylic acid chelating moiety, the highly sensitive fluorescent detection of uranium was successfully achieved. The detection limit of mid-ppt levels was determined, and coexisting matrix metal ions, such as Ca$$^{2+}$$, Co$$^{2+}$$, Cs$$^{+}$$, Sr$$^{2+}$$, lanthanide ions and others, do not disturb the detection of uranium. This method has a great potential to be applied to analysis of radioactive waste samples.

Oral presentation

Safe and rapid analytical methods for actinide ions and radioactive Sr-90 in high-dose radiation samples using fluorescent probes in capillary electrophoresis

Haraga, Tomoko; Nakano, Yuta*; Sato, Yoshiyuki; Ouchi, Kazuki*; Hirose, Kazuki*; Shibukawa, Masami*; Ishimori, Kenichiro; Kameo, Yutaka; Saito, Shingo*

no journal, , 

no abstracts in English

Oral presentation

Capillary electrophoresis with laser-induced fluorescence detection for ultratrace actinide ions in radioactive samples using emissive probes selected from a small chemical library

Haraga, Tomoko; Sato, Yoshiyuki; Ouchi, Kazuki; Shibukawa, Masami*; Ishimori, Kenichiro; Kameo, Yutaka; Saito, Shingo*

no journal, , 

no abstracts in English

Oral presentation

Capillary electrophoresis for detection of ultratrace uranyl ions in radioactive samples by way of fluorescent probe selection for actinide ions from a chemical library

Haraga, Tomoko; Ouchi, Kazuki; Sato, Yoshiyuki; Hoshino, Hitoshi*; Tanana, Rei*; Fujihara, Takashi*; Kurokawa, Hideki*; Shibukawa, Masami*; Ishimori, Kenichiro; Kameo, Yutaka; et al.

no journal, , 

no abstracts in English

Oral presentation

Supramolecular formation of humic acids via complexation with metal ion investigated by two dimensional gel electrophoresis

Marumo, Kazuki*; Saito, Takumi*; Haraga, Tomoko; Shibukawa, Masami*; Saito, Shingo*

no journal, , 

no abstracts in English

Oral presentation

Aggregation reaction analysis of humic acids via complexation with lanthanide and actinide ions by means of two dimensional gel electrophoresis

Marumo, Kazuki*; Saito, Takumi*; Haraga, Tomoko; Shibukawa, Masami*; Saito, Shingo*

no journal, , 

no abstracts in English

Oral presentation

Evaluation for molecular weight distribution of actinide ions complexed with humic acid by gel electrophoresis

Haraga, Tomoko; Marumo, Kazuki*; Saito, Takumi*; Shibukawa, Masami*; Saito, Shingo*

no journal, , 

no abstracts in English

18 (Records 1-18 displayed on this page)
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