Resumen de Nonlinear Fits of Standard Curves
A simple nonlinear least-squares method is described that permits direct least-squares fitting to the data of a standard curve to obtain the unknown concentration and its associated uncertainty. This procedure uses the unknown concentration as a parameter of the fit, so that it and its uncertainty are obtained immediately, bypassing the need to compute a propagation of interdependent uncertainties. Examples of the procedure, as implemented on Excel, are given for a standard additions analysis and for an analysis based on a standard calibration curve.
