title: Detection limit estimated from slope of calibration curve: an application to competitive ELISA.
abstract: This paper theoretically derives a general rule that while the slope of the semi-logarithmic plot (Y vs. log X) of a calibration curve varies depending on analyte concentration, X, the slope takes a specific value at the detection limit (L(D)). This rule holds good irrespective of the shape of the calibration curve (linear or non-linear) and in this paper, is applied to competitive ELISA (enzyme linked immunosorbent assay). The following relationship is deduced: slope of log-dose B/B0 at L(D) = [relative standard deviation (RSD) of blank responses] / 0.13. The L(D) obtained from the above-mentioned slope corresponds to the dose at which the RSD of dose estimates is 0.3 (= 30%). A commercial kit for 17alpha-hydroxyprogesterone is taken as an example.
authors.affiliation: National Institute of Health Sciences, 1-18-1 Kami-Yoga, Setagaya, Tokyo 153-8501, Japan.
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Hayashi
authors.forename: Rieko
authors.initials: R
authors.lastname: Matsuda
authors.forename: Katsutoshi
authors.initials: K
authors.lastname: Ito
authors.forename: Waka
authors.initials: W
authors.lastname: Nishimura
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Imai
authors.forename: Masako
authors.initials: M
authors.lastname: Maeda
mesh_terms: D019326:17-alpha-Hydroxyprogesterone / Q000032:analysis; D002138:Calibration; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D016015:Logistic Models; D008956:Models, Chemical; D012680:Sensitivity and Specificity
chemical_list: D019326:17-alpha-Hydroxyprogesterone