What is a standard curve?

A standard curve is a graphical representation of the relationship between known concentrations of a substance (e.g. a chemical compound, biomolecule, or analyte) and the corresponding values obtained from a measurement technique (e.g. absorbance, fluorescence intensity, or radioactivity).

Standard curves are commonly used in analytical chemistry, biochemistry, and molecular biology to quantify the concentration of an unknown sample. By plotting a series of known standard concentrations and measuring the response of the analytical technique, a line or curve can be generated to estimate the concentration of the unknown sample based on its measured value.

The shape of a standard curve can vary depending on the nature of the analyte and the measurement technique used. Common types of standard curves include linear, quadratic, and sigmoidal (non-linear) curves.

Standard curves are typically generated by performing a series of experiments with known concentrations of the analyte of interest in order to construct a calibration curve. This curve is then used to interpolate the concentration of unknown samples based on their measured values.

In order to ensure accurate and reliable results, it is important to properly prepare the standard solutions, calibrate the measurement instrument, and carefully follow the experimental protocol when constructing a standard curve. Additionally, it is important to verify the linearity and sensitivity of the assay by including appropriate controls and quality assurance measures.