Nomenclature in evaluation of analytical methods including detection and quantification capabilities (IUPAC Recommendations 1995)

Abstract

Abstract

Second- and higher-order data generation and calibration: A tutorial

“…and (3) it is needed to compute prediction uncertainties and detection capabilities [82]. According to the International Union of Pure and Applied Chemistry (IUPAC), the 902 sensitivity is well-defined in some analytical calibration [83][84][85], such as univariate 903 calibration, where it is the change in the instrument response for a unit change in the 904 concentration of the analyte of interest [83].…”

“…They can be estimated based on IUPAC's recommendations on the so-called 953 type I and II errors [82]. It is first required to define a critical concentration value, which 954 is the level for the detection decision, involving a certain risk of type I errors (is the 955 probability of false positive).…”

Validation Protocol: First Step of a Lean-Total Quality Management Principle in a New Laboratory Set-up in a Tertiary Care Hospital in India

“…It is the ability of an analytical method to assess small variations of the concentration of analyte [13]. This is often expressed as the slope of the calibration curve [14].…”

Modeling uncertainty in the measurement of low-level analytes in environmental analysis

“…As an example (zinc by ICPMS described in detail later), suppose that s e ¼ 204 (in units of the peak area), s Z ¼ 0:0390 (this is the high-level CV), a ¼ 490; and b ¼ 7:06: The derived quantities are S e ¼ 204=7:06 ¼ 28:9 ppt and S Z ¼ 0:0390: Then the standard deviation of blanks is 204 (units of peak area) or 28:9 ppt: Critical levels, which are the basis for determining detection of an analyte, are often set at 2-3 times the standard deviation of the blank above background (see Currie, 1995Currie, , 1997. Using this definition with a multiplier of 3, we have the critical level set at 490 þ 3ð204Þ ¼ 1102 in units of peak area or 3ð28:9 pptÞ ¼ 86:7 ppt: Then, using (2.4), the standard deviation of the response, y; at concentration m ¼ 86:7 ppt is That is, using the two-component model, measurements at this concentration have a standard deviation of B29:1 ppt; only slightly above the value for blanks, and RSD ¼ 29:1=86:7 ¼ 0:34:…”

“…The measurement error that exists in any technology leads to this inability to detect concentrations below a certain level. The critical level is defined by the International Union of Pure and Applied Chemistry (IUPAC) to be the value, L C ; such that the probability of a measurement exceeding this value will be very small, say 0.01, when the true concentration in the sample is zero (Currie, 1995). That is, samples that do not contain the analyte are very unlikely to generate measurement results that exceed L C : Note that the critical level is defined at first in the units of the measurement technology (e.g., peak area), not in units of concentration.…”