NETCHEM Method validation of zinc in wastewater by
NETCHEM Method validation of zinc in wastewater by AAS Part 4 – LOD and LOQ Author: Ph. D Ivana Mihajlović, assistant professor Institution: University of Novi Sad, Faculty of Technical Sciences, Department of Environmental Engineering, Trg Dositeja Obradovića 6, 21000 Novi Sad Course: Methodology of instrumental analysis of water and air ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Background • Educational objectives • To develop skills in statistical evaluation of data to verify the linearity of the calibration curve of the analytical method • To learn how to statistically process data to verify accuracy and precision of the analytical method • To master skills in calculation of LOD and LOQ of the analytical method ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Prerequisites • Students should: • familiarize themselves with basics of AAS technique • familiarize themselves with excel programme • see materials uploaded at the course's (http: //mdl. netchem. ac. rs/course/view. php? id=24) Moodle page
Make an excel sheet – LOD and LOQ - with table with data for statistical calculations ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Enter values for measured blank samples ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Calculate the difference in the measurement results of two analysts R=abs (B 12 -C 12) ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Calculate Xsr = AVERAGE(B 12: C 17) ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Calculate Rsr = AVERAGE (D 12: D 17) ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Calculate Sw Sw = F 13/F 14 ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Enter n (number of tests) and df (number of degrees of freedom) df = n-1 ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Calculate t value t = TINV(0. 05, 5) ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Calculate CD CD =F 18*F 15*SQRT(1+1/2) CD= t 0, 95(df)× Sw blank× (1+1/r)1/2 ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Calculate limit of detection (LOD) LOD=2*CD ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
Calculate limit of quantification (LOQ) LOQ=F 12+10*F 15 LOQ = Xsr, blank + 10 * Sw, blank ___________________________________________________ This project has been funded with support from the European Commission. This publication reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein.
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