start-ver=1.4
cd-journal=joma
no-vol=
cd-vols=
no-issue=
article-no=
start-page=
end-page=
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2021
dt-pub=2021
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Microfluidic Paper-based Analytical Devices Coupled with Coprecipitation Enrichment Show Improved Trace Analysis of Copper Ions in Water Samples
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=The present study was focused on improving sensitivity to trace levels of Cu(II) by subjecting microfluidic paper based analytical devices (μ PADs) to a preconcentration process via coprecipitation using aluminum hydroxide. The experimental conditions were optimized for the pH of the coprecipitation, centrifugation, and amounts of reagents that were deposited onto ? PADs for Cu(II) assay. The resultant limit of detection reached as low as 0.003 mg L 1 with a linear range of 0.01 2.00 mg L 1 . The relative standard deviations for intra and inter day precision were 3.2 and 4.6%, respectively (n = 9). Spiked water samples were analyzed using the μ PADs after coprecipitation preconcentration. The results were verified by comparing them with thos e of inductively coupled plasma optical emission spectrometry (ICP OES). Recoveries ranged from 97.1 104% and from 98.7 105% using the present method and ICP OES, respectively. These results suggest that the simple, highly sensitive, and inexpensive propos ed method would be helpful for analyzing trace levels of Cu(II) in water samples in poorly equipped laboratories.
en-copyright=
kn-copyright=

en-aut-name=MUHAMMEDAbdellah
en-aut-sei=MUHAMMED
en-aut-mei=Abdellah
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=HUSSENAhmed
en-aut-sei=HUSSEN
en-aut-mei=Ahmed
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=KanetaTakashi
en-aut-sei=Kaneta
en-aut-mei=Takashi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

affil-num=1
en-affil=Center for Environmental Science, College of Natural and Computational Sciences, Addis Ababa University
kn-affil=

affil-num=2
en-affil=Center for Environmental Science, College of Natural and Computational Sciences, Addis Ababa University
kn-affil=

affil-num=3
en-affil=Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University
kn-affil=
en-keyword=Microfluidic paper based analytical device
kn-keyword=Microfluidic paper based analytical device
en-keyword=Coprecipitation
kn-keyword=Coprecipitation
en-keyword=Preconcentration
kn-keyword=Preconcentration
en-keyword=Aluminum hydroxide
kn-keyword=Aluminum hydroxide
en-keyword=Copperion
kn-keyword=Copperion
en-keyword=bathocuproine
kn-keyword=bathocuproine
END

start-ver=1.4
cd-journal=joma
no-vol=21
cd-vols=
no-issue=3
article-no=
start-page=263
end-page=268
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2005
dt-pub=200503
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Trace and ultratrace analysis of purified water samples and hydrogen peroxide solutions for phosphorus by flow-injection method
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=<p>A highly sensitive fluorescence-quenching method for the determination of phosphorus based on the formation of an ion associate between molybdophosphate and Rhodamine B (RB) was developed. A simple flow-injection system coupled with a fluorescence detector was used to measure the fluorescence intensity at 560 nm and 580 nm as an excitation and an emission wavelength, respectively. The calibration graph for phosphorus showed a good linearity in the range of (0-1) x 10(-7) M (1 M = 1 mol L-1), and a detection limit of I x 10(-9) M (SIN = 3). The proposed method was successfully applied to the determination of ultratrace amounts of phosphorus in ultrapurified and purified water samples, and to the determination of trace amounts of phosphorus in commercially-available hydrogen peroxide solutions with satisfactory results.
en-copyright=
kn-copyright=

en-aut-name=LiZenhai
en-aut-sei=Li
en-aut-mei=Zenhai
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=OshimaMitsuko
en-aut-sei=Oshima
en-aut-mei=Mitsuko
kn-aut-name=大島光子
kn-aut-sei=大島
kn-aut-mei=光子
aut-affil-num=2
ORCID=

en-aut-name=SabarudinAkhmad
en-aut-sei=Sabarudin
en-aut-mei=Akhmad
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=MotomizuShoji
en-aut-sei=Motomizu
en-aut-mei=Shoji
kn-aut-name=本水昌二
kn-aut-sei=本水
kn-aut-mei=昌二
aut-affil-num=4
ORCID=

affil-num=1
en-affil=
kn-affil=Department of Chemistry, Faculty of Science, Okayama University

affil-num=2
en-affil=
kn-affil=Department of Chemistry, Faculty of Science, Okayama University

affil-num=3
en-affil=
kn-affil=Department of Chemistry, Faculty of Science, Okayama University

affil-num=4
en-affil=
kn-affil=Department of Chemistry, Faculty of Science, Okayama University
END