Determination of metal ions by capillary zone electrophoresis with on-column chelation using 8-hydroxyquinoline-5-sulfonic acid

Swaile, David F.; Sepaniak, Michael J.

doi:10.1021/ac00002a017

Cited by 141 publications

(36 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fluorescence was collected through a 500-nm (500DF25) band pass filter (Omega Optical, Brattleboro, VT, USA). Detection limits comparable to those of Swaile and Sepaniak 15 were achieved for the determination of metals using HQS (see below).…”

Section: Apparatusmentioning

confidence: 74%

“…Swaile and Sepaniak attributed this peak broadening to a slow rate of ligand exchange, 15 an effect known as electrodiffusion. 3 The effect of electrodiffusion can be reduced by increasing the HQS concentration.…”

Section: Hqs Detection Of Metalsmentioning

confidence: 99%

“…However, increasing the HQS concentration leads to an unacceptably high background fluorescence. 15,18 Alternatively, both the formation and dissociation rates can be increased by increasing the capillary temperature. 18 A third approach to reducing electrodiffusion, and the one used herein, is to add the complexing ligand to the sample.…”

Section: Hqs Detection Of Metalsmentioning

confidence: 99%

“…Optimum excitation of the metal-HQS is at 393 nm with maximum emission in the 500 -520 nm range. 17 Fluorescence excitation of metal-HQS complexes separated by CE has been performed using the 325 nm HeCd laser line, 15,18,19 the 351.1 -364.8 nm lines of an argon ion laser 20 and with a broad band mercury-xenon lamp. 16 However, none of these excitation sources is ideal.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Violet Diode Laser for Metal Ion Determination by Capillary Electrophoresis-Laser Induced Fluorescence

Vos

Lucy

2001

ANAL. SCI.

View full text Add to dashboard Cite

Since the work of Jorgenson and Lukacs in the early 1980s, 1,2 capillary electrophoresis (CE) has experienced rapid growth and been applied to a wide array of analytes. The dominant area of application of CE has been for biomolecules. However, there has been a steady and increasing interest in using CE for the determination of metal ions. 3The attractive features of CE for metal ion determination are the same as those for other separations: its exceptional separation efficiency; its rapid separations; and its low mass detection limits. However, as with other types of analytes, the primary limitation of CE is its poor concentration detection limits. Most (85%) publications of CE for metal ions have used absorbance detection. 3 Unfortunately, few hydrated metal ions absorb significantly above 185 nm. Greater sensitivity is achieved by complexing the metal ions with a metallochromic dye. Examples include PAR for transition metals, 4 Arsenazo I for alkaline earth metals 5 and Arsenate III for lanthanides and uranium. 6,7 Alternatively, up to 26 metal cations have been separated with parts-per-billion detection limits using indirect absorbance detection. [8][9][10][11] Regardless, the most sensitive detection scheme in CE is laser induced fluorescence (LIF). 12-14 CE-LIF determinations of metals typically use the 8-hydroxyquinoline-5-sulfonic acid (HQS) fluorescent ligand shown in Fig. 1 . Optimum excitation of the metal-HQS is at 393 nm with maximum emission in the 500 -520 nm range. 17 Fluorescence excitation of metal-HQS complexes separated by CE has been performed using the 325 nm HeCd laser line, 15,18,19 the 351.1 -364.8 nm lines of an argon ion laser 20 and with a broad band mercury-xenon lamp. 16 However, none of these excitation sources is ideal. They all are expensive and have limited lifetimes (∼5000 h). They are also relatively bulky, making them unattractive for miniaturized instruments. 19 Semiconductor or diode lasers are promising alternatives to conventional lasers. Diode lasers are cheap, require no maintenance, and have lifetimes approaching 50000 h. 21 These lasers are also extremely compact and can run off battery power.Further, the output stability of diode lasers is significantly better than that of conventional lasers (0.01% vs. 1% noise). 22 These properties suggest that diode lasers are ideally suited for LIF detection. In October of 1999, Nichia Corporation (Japan) launched the commercial sale of their InGaN-based violet laser diode.23-27 * The diode operates at 405 nm with a power output of 5 mW and has an estimated lifetime of 2000 to 5000 h. Such short wavelength semiconductor lasers have long been sought for applications such as full-color electroluminescent displays, laser printers, undersea optical communications and optical data storage. For instance, a violet diode laser would quadruple the data capacity of current DVD players.In addition to its applications in electronics and telecommunications, the violet diode laser offers tremendous potential for analytical chemistry. Recently, ...

show abstract

Section: Apparatusmentioning

confidence: 74%

Section: Hqs Detection Of Metalsmentioning

confidence: 99%

Section: Hqs Detection Of Metalsmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Violet Diode Laser for Metal Ion Determination by Capillary Electrophoresis-Laser Induced Fluorescence

Vos

Lucy

2001

ANAL. SCI.

View full text Add to dashboard Cite

show abstract

“…Swaile and Sepaniak [30] reported the separation of Ca (11), Mg (11), and Zn (11) with the chelating agent, 8-hydroxyquinoline-5-sulfonic acid (HQSH). In aqueous solution, the anion, HQS-, is formed and binds with metal ions to form fluorescent complexes.…”

Section: Direct Detectionmentioning

confidence: 99%