![Developing a sequential injection-square wave voltammetry (SI-SWV) method for determination of atrazine using a hanging mercury drop electrode [An article from: Analytica Chimica Acta]](https://www.ebooknetworking.net/books/B00/0RR/bigB000RR3FOO.jpg)
Developing a sequential injection-square wave voltammetry (SI-SWV) method for determination of atrazine using a hanging mercury drop electrode [An article from: Analytica Chimica Acta]
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This digital document is a journal article from Analytica Chimica Acta, published by Elsevier in 2005. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description:
This paper describes the development of a sequential injection analysis method to automate the determination of atrazine by square wave voltammetry exploiting the concept of monosegmented flow analysis to perform in-line sample conditioning and standard addition. To perform these tasks, an 800@mL monosegment is formed, composed by 400@mL of sample and 400@mL of buffer/standard solution. To obtain an efficient homogenization, the sample solution is divided in five zones intercalated by four zones of the Britton-Robinson buffer (pH 2.0) in presence of appropriate concentration of NaNO"3 and varying atrazine standard concentrations. This mixture zone is isolated from the carrier solution by two 100@mL air bubbles. After homogenization in an auxiliary reaction coil the mixture zone is injected toward the flow cell, which is adapted to the capillary of a hanging drop mercury electrode, at a flow rate of 50@mLs^-^1. After a suitable delay time, the potential is scanned from -0.5 to -1.2V versus Ag/AgCl using a frequency of 300Hz and pulse height of 25mV. The linear dynamic range is observed for atrazine concentrations between 1.16x10^-^7 and 2.32x10^-^6molL^-^1, obeying the linear equation i"p=(-6.91+/-0.07)x10^8[atrazine]+(4+/-8), with r^2=0.9996, for which the slope is given in nALmol^-^1. The detection and quantification limits of the method are 2.1x10^-^8 and 7.0x10^-^8molL^-^1, respectively. The sampling frequency is 37h^-^1, when the standard addition protocol is followed. This frequency can be increased to 42h^-^1 if the protocol to obtain in-line calibration curve is used for quantification. The method was applied for determination of atrazine in spiked river water samples and its accuracy was evaluated by comparison with the batch standard addition approach, which revealed that there is no evidence of statistically significant differences between the two methods.
Description:
This paper describes the development of a sequential injection analysis method to automate the determination of atrazine by square wave voltammetry exploiting the concept of monosegmented flow analysis to perform in-line sample conditioning and standard addition. To perform these tasks, an 800@mL monosegment is formed, composed by 400@mL of sample and 400@mL of buffer/standard solution. To obtain an efficient homogenization, the sample solution is divided in five zones intercalated by four zones of the Britton-Robinson buffer (pH 2.0) in presence of appropriate concentration of NaNO"3 and varying atrazine standard concentrations. This mixture zone is isolated from the carrier solution by two 100@mL air bubbles. After homogenization in an auxiliary reaction coil the mixture zone is injected toward the flow cell, which is adapted to the capillary of a hanging drop mercury electrode, at a flow rate of 50@mLs^-^1. After a suitable delay time, the potential is scanned from -0.5 to -1.2V versus Ag/AgCl using a frequency of 300Hz and pulse height of 25mV. The linear dynamic range is observed for atrazine concentrations between 1.16x10^-^7 and 2.32x10^-^6molL^-^1, obeying the linear equation i"p=(-6.91+/-0.07)x10^8[atrazine]+(4+/-8), with r^2=0.9996, for which the slope is given in nALmol^-^1. The detection and quantification limits of the method are 2.1x10^-^8 and 7.0x10^-^8molL^-^1, respectively. The sampling frequency is 37h^-^1, when the standard addition protocol is followed. This frequency can be increased to 42h^-^1 if the protocol to obtain in-line calibration curve is used for quantification. The method was applied for determination of atrazine in spiked river water samples and its accuracy was evaluated by comparison with the batch standard addition approach, which revealed that there is no evidence of statistically significant differences between the two methods.
