Search results for: Luz O. Leal
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A 3D printed device for the fully automated disk-based solid-phase extraction (SPE) of Cr (VI) from water samples has been fabricated. The compatibility of the use of organic solvents for analyte elution with 3D printed flow devices based on polymers fabricated using stereolithography has been evaluated. The developed methodology comprises the complexation of Cr (VI) with 1, 5-diphenylcarbazide (DPC)...
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The development of advanced manufacturing techniques is crucial for the design of novel analytical tools with unprecedented features. Advanced manufacturing, also known as 3D printing, has been explored for the first time to fabricate modular devices with integrated features for disk-based automated solid-phase extraction (SPE). A modular device integrating analyte oxidation, disk-based SPE and analyte...
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Microchemical Journal > 2017 > 132 > C > 107-111
A miniaturized automatic sample pre-treatment system, based on multicommutated flow techniques, i.e. Lab on Valve (LOV) and Multisyringe Flow Injection Analysis (MSFIA) techniques, for cadmium determination by ICP-MS in organic samples is presented. The on-line extraction and preconcentration system retains the analyte on the resin (Dowex 50W-X8), followed of elution with 1molL−1 HNO3. The LOV-MSFIA...
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TrAC Trends in Analytical Chemistry > 2016 > 76 > C > 145-152
Radionuclides monitoring is an issue of increasing concern due to their widespread use last years. Thus, efficient methods for radionuclides determination are required. Radionuclides extraction and preconcentration is usually required prior detection, especially when dealing with environmental and biological samples. Most commonly pretreatment techniques in radiochemical analysis are solid-phase extraction...
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A new automatic kinetic catalytic method has been developed for the measurement of Mn2+ in drinking and seawater samples. The method is based on the catalytic effect of Mn2+ on the oxidation of tiron by hydrogen peroxide in presence of Pb2+ as an activator. The optimum conditions were obtained at pH 10 with 0.019molL−1 2'2 bipyridyl, 0.005molL−1 tiron and 0.38molL−1 hydrogen peroxide. Flow system...
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A fully automated in-syringe (IS) magnetic stirring assisted (MSA) liquid-liquid microextraction (LLME) method for uranium(VI) determination was developed, exploiting a long path-length liquid waveguide capillary cell (LWCC) with spectrophotometric detection. On-line extraction of uranium was performed within a glass syringe containing a magnetic stirrer for homogenization of the sample and the successive...
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A novel lab-on-valve system has been developed for strontium determination in environmental samples. Miniaturized lab-on-valve system potentially offers facilities to allow any kind of chemical and physical processes, including fluidic and microcarrier bead control, homogenous reaction and liquid–solid interaction. A rapid, inexpensive and fully automated method for the separation and preconcentration...
