Flow injection analysis of nitrogen dioxide using a galvanic detector

A flow injection configuration (FIA) based on a galvanic detector for the determination of nitrogen dioxide is described. The gaseous sample is directly injected into a gaseous carrier. The sample is transported toward the detector. The steady state measurements are not required to obtain the reproducible peak signals. The features of FIA are compared with that of continuous flow monitoring application. The flow injection system is simple, rapid and capable of detecting NO2in the range of 1-500 ppm (v/v). The measuring range and sensitivity of the galvanic detector in FIA depend on the sample volume. A relative standard deviation is 2.4%(n=10)for 200 ppm (v/v) of nitrogen dioxide. The sampling frequency is about 24 h-1

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Determination of Picogram Levels of Roxithromycin in Pharmaceutical, Human Serum, and Urine by Flow-Injection Chemiluminescence

ISRN Analytical Chemistry ◽

10.5402/2012/101092 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5

Author(s):

Jiangman Liu ◽

Huan Yang ◽

Yun Zhang ◽

Min Wu ◽

Haixiang Zhao ◽

...

Keyword(s):

Human Serum ◽

Flow Injection ◽

Limit Of Detection ◽

Inhibitory Effect ◽

Injection System ◽

Relative Standard ◽

Flow Injection System ◽

Flow Injection Chemiluminescence ◽

Serum And Urine

A sensitive chemiluminescence (CL) method, based on the inhibitory effect of roxithromycin (ROX) on the CL reaction between luminol and dissolved oxygen in a flow-injection system, was first proposed for the determination of ROX at picogram levels. The decrement of CL intensity was linearly proportional to the logarithm of ROX concentrations ranging from 0.1 to 100 pg mL-1, giving the limit of detection (LOD) of 0.03 pg mL-1 (3σ). At a flow rate of 2.0 mL min-1, a complete analytical procedure including sampling and washing could be performed within 0.5 min, with relative standard deviations (RSDs) of less than 5.0% (n=5). The proposed procedure was applied successfully to the determination of ROX in pharmaceutical, human serum, and urine with the recoveries ranging from 90.0 to 110.0%.

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Direct determination of calcium in milk by atomic absorption spectrometry using flow-injection analysis

Eclética Química ◽

10.1590/s0100-46702007000300004 ◽

2007 ◽

Vol 32 (3) ◽

pp. 25-30 ◽

Cited By ~ 3

Author(s):

M. B. Petrovich ◽

V. R. A. Filho ◽

J. A. G. Neto

Keyword(s):

Reference Materials ◽

Flow Injection ◽

Direct Determination ◽

Absorption Spectrometry ◽

Sample Volume ◽

Standard Reference Materials ◽

Injection System ◽

Relative Standard ◽

Flow Injection System ◽

Assisted Decomposition

A flow-injection system with sample and reagent addition by the synchronous merging zones approach for calcium determination in milk by flame AAS is proposed. Main parameters were optimized using a factorial design with central point. The optimum conditions were 2.5% (m/v) for La concentration, 8 mL min-1 for the carrier flow-rate, 20 cm for coiled reactor and 250 ìL for sample volume. Different sample preparation procedures were evaluated such as dilution in water or acid and microwave-assisted decomposition using concentrated or diluted acids. The optimized flow system was applied to determine Ca in eleven commercial milk samples and two standard reference materials diluted in water. Similar calcium levels were encountered comparing the results obtained by the proposed method (dilution in water) with those obtained using microwave-oven digestion. Results obtained in two standard reference materials were in agreement at 95% confidence level with those certified. Recoveries of spiked samples were in the 93% - 116% range. Relative standard deviation (n = 12) was < 5.4% and the sample throughput was 150 measurements per hour, corresponding to a consumption of 250 µL of sample and 6.25 mg La per determination.

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The application of the chromatomembrane cell for the absorptive sampling of nitrogen dioxide followed by continuous determination of nitrite using a micro-flow injection system

Talanta ◽

10.1016/s0039-9140(02)00026-7 ◽

2002 ◽

Vol 57 (2) ◽

pp. 355-364 ◽

Cited By ~ 22

Author(s):

Y WEI ◽

M OSHIMA ◽

J SIMON ◽

S MOTOMIZU

Keyword(s):

Nitrogen Dioxide ◽

Flow Injection ◽

Injection System ◽

Micro Flow ◽

Flow Injection System ◽

Continuous Determination

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Determination of Hesperetin in Pericarpium Citri Reticulatae and Human Serum Using Flow Injection Chemiluminescence

ISRN Analytical Chemistry ◽

10.5402/2012/809256 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5

Author(s):

Jiajia Wang ◽

Xijuan Tan ◽

Xin Li ◽

Jiangman Liu ◽

Zhenghua Song

Keyword(s):

Dissolved Oxygen ◽

Human Serum ◽

Flow Injection ◽

Inhibitory Effect ◽

Injection System ◽

Sampling Efficiency ◽

Relative Standard ◽

Flow Injection System ◽

Flow Injection Chemiluminescence

A sensitive chemiluminescence (CL) method for the determination of hesperetin at nanogram levels was first presented. It was based on the inhibitory effect of hesperetin on luminol-dissolved oxygen CL reaction in a flow injection system. The decrements of CL intensity were logarithm over the concentrations of hesperetin in a range of 0.5 to 1000 ng mL−1, with a detection limit of 0.2 ng mL−1 (3σ) and the relative standard deviations lower than 2.1%. At a flow rate of 2.0 mL min−1, the whole determining performance including sampling and washing could be accomplished in 30 s, giving a sampling efficiency of 120 h−1. The proposed method was applied successfully to the direct hesperetin determination in human serum with recoveries from 97.0 to 106.6%, and indirect hesperidin quantification in 2.5 g pericarpium citri reticulatae showing that the content is 8.1±0.2%. The possible CL mechanism of luminol-dissolved oxygen-hesperetin reaction was also discussed in detail.

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