Optimization of a Spectrophotometric Flow Injection

This chapter presents the optimization of the hydrodynamic and chemical parameters of the FIA system in the determination of copper and manganese in wine samples by VIS spectrophotometry. This technique has been based on the injection of liquid samples in the non-segmented movement, within a continuous carrier current of a suitable liquid. The injected sample forms a zone that disperses on its way to a detector. The later continuously records the absorbance or other physical parameters, since it continuously passes the sample material through the flow cell, using the factorial designs Plackett-Burman, Box-Behnken, and the factorial design 2^4. The methods have the advantages of low-cost, easy availability of chemicals, and instrumentation and straightforward application to real samples.

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Applicability of Cork as Novel Modifiers to Develop Electrochemical Sensor for Caffeine Determination

Materials ◽

10.3390/ma14010037 ◽

2020 ◽

Vol 14 (1) ◽

pp. 37

Author(s):

Mayra K. S. Monteiro ◽

Djalma R. Da Silva ◽

Marco A. Quiroz ◽

Vítor J. P. Vilar ◽

Carlos A. Martínez-Huitle ◽

...

Keyword(s):

Electrochemical Sensor ◽

Linear Response ◽

High Performance ◽

Low Cost ◽

Pharmaceutical Formulations ◽

Caffeine Concentration ◽

Real Samples ◽

Wide Range ◽

Potential Use

This study aims to investigate the applicability of a hybrid electrochemical sensor composed of cork and graphite (Gr) for detecting caffeine in aqueous solutions. Raw cork (RAC) and regranulated cork (RGC, obtained by thermal treatment of RAC with steam at 380 °C) were tested as modifiers. The results clearly showed that the cork-graphite sensors, GrRAC and GrRGC, exhibited a linear response over a wide range of caffeine concentration (5–1000 µM), with R2 of 0.99 and 0.98, respectively. The limits of detection (LOD), estimated at 2.9 and 6.1 µM for GrRAC and GrRGC, suggest greater sensitivity and reproducibility than the unmodified conventional graphite sensor. The low-cost cork-graphite sensors were successfully applied in the determination of caffeine in soft drinks and pharmaceutical formulations, presenting well-defined current signals when analyzing real samples. When comparing electrochemical determinations and high performance liquid chromatography measurements, no significant differences were observed (mean accuracy 3.0%), highlighting the potential use of these sensors to determine caffeine in different samples.

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Metal–organic framework based micro solid phase extraction coupled with supramolecular solvent microextraction to determine copper in water and food samples

New Journal of Chemistry ◽

10.1039/c8nj00340h ◽

2018 ◽

Vol 42 (8) ◽

pp. 5806-5813 ◽

Cited By ~ 9

Author(s):

Rohullah Kashanaki ◽

Homeira Ebrahimzadeh ◽

Morteza Moradi

Keyword(s):

Solid Phase Extraction ◽

Solid Phase ◽

Metal Organic Framework ◽

Food Samples ◽

Phase Extraction ◽

Real Samples ◽

Supramolecular Solvent ◽

Metal Organic ◽

Determination Of Copper

D-μ-SPE-SUPRAS-ME followed by GFAAS was successfully used for preconcentration and determination of copper in real samples.

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Kinetic-potentiometric determination of copper in real samples with a new antimony(V) ion-selective electrode

Fresenius Journal of Analytical Chemistry ◽

10.1007/bf00325122 ◽

1992 ◽

Vol 344 (3) ◽

pp. 100-103 ◽

Cited By ~ 8

Author(s):

C. S�nchez-Pedre�o ◽

J. A. Ortu�o ◽

J. Martinez-R�denas

Keyword(s):

Ion Selective Electrode ◽

Potentiometric Determination ◽

Selective Electrode ◽

Real Samples ◽

Determination Of Copper

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Flow Injection Spectrophotometric Determination of Copper, Iron, Manganese, and Zinc in Animal Feeds Using a Common Manifold

Journal of AOAC International ◽

10.1093/jaoac/83.6.1293 ◽

2000 ◽

Vol 83 (6) ◽

pp. 1293-1298 ◽

Cited By ~ 5

Author(s):

Jing-Fu Liu ◽

Gui-Bin Jiang ◽

Ying-Di Feng

Keyword(s):

Flow Injection ◽

Simple Procedure ◽

Xylenol Orange ◽

Low Cost ◽

Injection System ◽

Animal Feeds ◽

Flow Injection System ◽

Iron Manganese ◽

Determination Of Copper

Abstract A rapid and simple procedure was developed for the determination of copper, iron, manganese, and zinc in animal feeds using an identical flow injection spectrophotometric manifold but different chromogenic reagents and different detection wavelengths. Bis(cyclohexanone)oxalydihydrazone, formaldoxime, 1,10-phenanthroline, and xylenol orange were adopted as chromogenic reagents for Cu, Mn, Fe, and Zn, respectively. Detection conditions such as manifold parameters, buffer pH, reagent concentration, temperature, and acidity of sample solution were optimized. Analytical characteristics of the method and interference of metal ions commonly present in feeds were studied. By changing the reagents and detection wavelengths, which can be done quickly, the proposed low cost flow injection system can determine Cu, Fe, Mn, or Zn in the range of 0.5–10 mg/L with a sampling throughput of 120/h.

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Determination of Trace Copper with Sulfophenylazo Rhodanine by Catalytic Dynamic Spectrofluorimetry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.710.112 ◽

2013 ◽

Vol 710 ◽

pp. 112-116

Author(s):

Yuan Na Zhu ◽

Ya Ming Chen ◽

Shen Guang Ge ◽

Jing Hua Yu

Keyword(s):

Fluorescent Property ◽

Optimum Conditions ◽

Real Samples ◽

Molecule Structure ◽

New Methods ◽

The Relationship ◽

Determination Of Copper

Series new methods were established which were based on the research of determination of trace copper with four sulfophenylazo rhodanine derivatives by catalytic dynamic spectrofluorimetry under the optimum conditions. This proposed method was applied to the determination of copper in real samples with satisfactory results. According to experiment results, the influences of different active groups and substitution positions on fluorescent property of rhodanine derivatives were investigated and the relationship between molecule structure and fluorescent property was explored.

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