Source: Laboratory of Dr. Paul Bower - Purdue University
The method of standard additions is a quantitative analysis method, which is often used when the sample of interest has multiple components that result in matrix effects, where the additional components may either reduce or enhance the analyte absorbance signal. That results in significant errors in the analysis results.
Standard additions are commonly used to eliminate matrix effects from a measurement, since it is assumed that the matrix affects all of the solutions equally. Additionally, it is used to correct for the chemical phase separations performed in the extraction process.
The method is performed by reading the experimental (in this case fluorescent) intensity of the unknown solution and then by measuring the intensity of the unknown with varying amounts of known standard added. The data are plotted as fluorescence intensity vs. the amount of the standard added (the unknown itself, with no standard added, is plotted ON the y-axis). The least squares line intersects the x-axis at the negative of the concentration of the unknown, as shown in Figure 1.
1Department of Surgery and Translational Medicine (DCMT), University of Florence, 2Neurofarba Department, University of Florence, 3Department of Traumatology and General Orthopedics, Azienda Ospedaliera Universitaria Careggi
1Department of Biomedical Sciences, Dr. William M Scholl College of Podiatric Medicine, Rosalind Franklin University of Medicine and Science, 2Department of Cell Biology and Anatomy, Rosalind Franklin University of Medicine and Science
1Department of Geosciences, University of Tuebingen, 2Department of Geological and Atmospheric Sciences, Iowa State University
1Fachbereich Biologie, Entwicklungsbiologie, Philipps-Universität Marburg, 2Institut für Molekularbiologie und Tumorforschung, Philipps-Universität Marburg
1INSERM U1051, Institut des Neurosciences de Montpellier (INM), Université de Montpellier, 2Université de Nîmes, 3CNRS, IES, UMR 5214, 4Aix-Marseille Université, CNRS,
École Centrale Marseille, Institut Fresnel, UMR 7249, 5Montpellier RIO Imaging (MRI)
1CanmetENERGY, Natural Resources Canada
1Center for Advanced Biotechnology and Medicine, Rutgers University, 2Department of Neuroscience and Cell Biology, Rutgers University
1Bioenergy Research Unit, National Center for Agricultural Utilization Research, 2Mycotoxin Prevention and Applied Microbiology Research Unit, National Center for Agricultural Utilization Research, 3Chemical Engineering and Material Science, Great Lakes Bioenergy Center, Michigan State University
1Université Claude Bernard Lyon, 2Centre de Génétique et de Physiologie Moléculaires et Cellulaires, CNRS UMR 5534
1Experimental Radiology, Institute of Diagnostic and Interventional Radiology I, Jena University Hospital, 2Department of Pharmaceutical Technology, Friedrich-Schiller-University Jena, 3Center for Electron Microscopy, Jena University Hospital
1Quinze-Vingts National Ophthalmology Hospital, 2INSERM UMR S 968, Institut de la Vision, 3Sorbonne Universités, UPMC Univ Paris 06, 4CNRS, UMR 7210
1Stem Cell Institute, Katholieke Universiteit Leuven
1Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center and Research Institute
1Epigenetics and Cell Fate, UMR 7216 CNRS, Centre National de la Recherche Scientifique CNRS - Université Paris Diderot, Sorbonne Paris Cité
1Division of Rheumatology, Immunology, and Allergy, Brigham and Women's Hospital, 2Department of Medicine, Harvard Medical School, 3Department of Histology and Embryology, Poznan University of Medical Sciences, 4The Broad Institute of Harvard and M.I.T.
1Institute of Industrial Science, The University of Tokyo, 2Micro Analysis Laboratory, Tandem accelerator, The University Museum, The University of Tokyo
1Institute of Neuronal Cell Biology, Technische Universität München, 2Cell Biology, Department of Biology, Faculty of Science, Utrecht University, 3Faculty of Biology, Ludwig-Maximilians-Universität-München, 4Adolf-Butenandt-Institute, Biochemistry, Ludwig-Maximilians-Universität-München, 5German Center for Neurodegenerative Diseases, 6Laboratory of Brain Development and Repair, The Rockefeller University
1Institute for Biochemistry and Molecular Biology, Ulm University
1School of Physics and Astronomy, University of Southampton, 2Department of Physics, University of Warwick, 3Institut des Matériaux Jean Rouxel, University of Nantes CNRS