This is defined as \[K = \frac{Q_{\rm{T}}/Q_{\rm{M}}}{Q_{\rm{T}}^{\rm{o}}/Q_{\rm{M}}^{\rm{o}}}\] where \(Q_{\rm{T}}\) and \(Q_{\rm{T}}^{\rm{o}}\) are the quantities of the microcomponent in the concentrate and in the sample, respectively (mass units or concentration units), and \(Q_{\rm{M}}^{\rm{o}}\) and \(Q_{\rm{M}}\) and are the quantities of the matrix before and after preconcentration, respectively. If the recovery is 100%, \(K=\frac{Q_{\rm{M}}^{\rm{o}}}{Q_{\rm{M}}}\). The terms enrichment coefficient and enrichment factor are not recommended.