Tutorial review on validation of liquid chromatography–mass spectrometry methods: Part II

Occurrence of Chiral Bioactive Compounds in the Aquatic Environment: A Review

“…For example, cleanup during sample preparation is very important to avoid large amounts of co-extracted matrix constituents [58]. In the case of environmental matrices, they are complex and present high variability, and even the same type of matrix collected in different locations and/or time, may have different composition [56]. Chiral analysis encompasses an additional challenge because different matrix effect may arise for a pair of enantiomers.…”

“…This struggle highlights the significance of an efficient clean-up during the sample preparation in order to eliminate interferences and therefore reduce the matrix effects that negatively affect selectivity and limits of quantification [56]. Matrix effect can be caused by endogenous compounds (e.g., humic or fluvic acids, lipids, among others) or exogenous compounds resulting from the analytical method (e.g., as salts or other reagents added to the matrix), that can originate enhancement or more frequently suppression of the analytical signal (e.g., GC-MS or LC-MS).…”

Validation of Ion Chromatographic Method for Determination of Standard Inorganic Anions in Treated and Untreated Drinking Water

“…Three spiked reagent blanks at the low concentration levels were prepared for this study, each sample was analyzed in triplicate and the means are used to calculate standard deviation. The standard deviation (in mg/L) was divided by the square root of the number of measurements; (2) calculation based on 3.3 or 10 times the standard deviation of residuals divided by the slope of standard curve [16,17]. Table 4.…”

“…Calculation based on the SD of the lowest concentration [14] Calculation based on SD of the residuals [16,17] LOD and LOQ in water samples [14]. The repeatability test was made for a short period, by the same user with the same instrument.…”

“…A line of studies on optimisation and validation of ion chromatographic methods for anions determination have been recently published [7][8][9][10][11][12][13]. The validation procedure was profoundly described in the international legislation to ensure comparable laboratory results [14][15][16][17].The validation should prove that the results obtained by given laboratory were not significantly different from the reference results [16,17].Validation of a method for chloride, nitrate and sulphate ions determination in drinking water was reported [12]; all contributions involved in the analysis were considered in estimation of the uncertainty. A validation of an ion chromatographic methods for determination of fluoride, chloride, nitrite, bromide, nitrate, phosphate and sulphate anions in wet depositions and other meteoric water sources with precision less than 2 % was described [11].…”